Free5gc CVEs & Vulnerabilities

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-pfdmanagement route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can use a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token) to read PFD application data via GET /applications and GET /applications/{appID}, and to create or delete PFD change-notification subscriptions via POST /subscriptions and DELETE /subscriptions/{subID}. Same root cause as the other NEF SBI findings: the route group is mounted without any inbound auth middleware. Unlike the OAM and traffic-influence groups, nnef-pfdmanagement IS declared in the runtime ServiceList, so this is the production-intended path that operators expect to be protected by OAuth2 setting receive from NRF: true -- and it is not. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without OAuth2/bearer-token authorization middleware. A network attacker who can reach SMF on the SBI can hit UPI endpoints with no Authorization header at all, and the requests reach the SMF business handlers. In the running Docker lab this was directly demonstrated for read (GET /upi/v1/upNodesLinks), write (POST /upi/v1/upNodesLinks with attacker-controlled UP-node and link payload), and delete (DELETE /upi/v1/upNodesLinks/{nodeID}) operations. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. On top of that, the DELETE /upi/v1/upNodesLinks/{upNodeRef} handler unconditionally dereferences upNode.UPF after the type-guarded async release, even though AN-typed nodes are constructed without a UPF object. As a result, a single unauthenticated DELETE /upi/v1/upNodesLinks/gNB1 request crashes the handler with a nil-pointer panic AND mutates the in-memory user-plane topology before panicking (the UpNodeDelete(upNodeRef) line runs first). This is an unauthenticated, state-mutating panic-DoS sink that an off-path network attacker can trigger by name against any AN entry. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-oam route group without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can hit the OAM route with no Authorization header at all and the handler returns 200 OK. The current OAM handler is a stub that returns null, but the structural defect is route-group-scoped: the entire OAM route group has no inbound auth middleware, so every future OAM operation added to this group inherits the missing auth boundary by default. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-traffic-influence API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, patch, and delete traffic-influence subscriptions either with no Authorization header at all, or with a forged bearer token (e.g. Authorization: Bearer not-a-real-token). This includes creating AnyUeInd=true subscriptions intended to affect group / any-UE traffic steering. The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NRF root SBI endpoint POST /oauth2/token contains a parser-level type-confusion bug family. The handler in NFs/nrf/internal/sbi/api_accesstoken.go reflects over models.NrfAccessTokenAccessTokenReq, special-cases only plain string and NrfNfManagementNfType fields, and treats every other field as if it were a single models.PlmnId. The parsed *models.PlmnId is then assigned with reflect.Value.Set() to whichever field name the attacker put in the form body, which panics whenever the destination field's real type is incompatible (slice, different struct, primitive). Gin recovery converts each panic into HTTP 500, but the endpoint remains remotely panicable from a single unauthenticated form-encoded request and is repeatedly triggerable. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's UDR nudr-dr DELETE /subscription-data/{ueId}/{servingPlmnId}/ee-subscriptions/{subsId}/amf-subscriptions handler panics on a single authenticated request against a fresh UDR instance when the supplied ueId does not exist in UESubsCollection. The processor checks value, ok := udrSelf.UESubsCollection.Load(ueId) and sets a 404 USER_NOT_FOUND problem-details on the miss path, but execution continues and immediately runs value.(*udr_context.UESubsData) -- a Go type assertion on a nil interface, which panics with interface conversion: interface {} is nil, not *context.UESubsData. Gin recovery converts the panic into HTTP 500, but the endpoint remains repeatedly panicable. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's UDR nudr-dr DELETE /subscription-data/{ueId}/{servingPlmnId}/ee-subscriptions/{subsId}/amf-subscriptions handler contains a nil-pointer dereference reachable from a single authenticated request, after one preparatory authenticated EE-subscription create. The handler checks _, ok = UESubsData.EeSubscriptionCollection[subsId] and sets a 404 problem-details on the miss path, but then continues to UESubsData.EeSubscriptionCollection[subsId].AmfSubscriptionInfos -- dereferencing the same missing entry instead of returning. Gin recovery converts the panic into HTTP 500, but the endpoint remains repeatedly panicable. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF PATCH /3gpp-pfd-management/v1/{afId}/transactions/{transId}/applications/{appId} handler panics with a nil-pointer dereference when the upstream UDR call fails AND the consumer wrapper returns err != nil together with a nil *ProblemDetails. The handler's errPfdData != nil branch builds its own problemDetailsErr correctly, but immediately after it reads problemDetails.Cause (the OTHER value, which is nil in this branch) and panics. Gin recovery converts the panic into HTTP 500, so a single PATCH against this endpoint returns 500 instead of the intended controlled error response whenever UDR access is failing. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's SMF mounts the UPI management route group without inbound OAuth2 middleware. The POST /upi/v1/upNodesLinks create-or-update handler accepts attacker-controlled JSON and passes it directly into UpNodesFromConfiguration(), which calls logger.InitLog.Fatalf(...) on several validation failures. One confirmed path is the UE-IP-pool overlap check: a single unauthenticated POST that adds a new UPF whose pool overlaps an existing UPF terminates the entire SMF process (docker ps shows Exited (1)), not just the goroutine. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the nnef-callback route group without inbound OAuth2/bearer-token authorization. A forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token) is enough to reach the SMF-callback handler -- the callback body is parsed and dispatched into NEF business logic instead of being rejected at the auth boundary. Same root cause as the other NEF SBI findings: the route group is mounted without any inbound auth middleware. NEF does not authenticate the producer NF identity before processing callback content; if an attacker can guess or obtain a valid NotifId, this missing auth boundary lets forged callbacks act on real subscription state. The route group is also reachable even when the runtime ServiceList does not declare it (it lists only nnef-pfdmanagement and nnef-oam). This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF terminates the entire process when a stored PFD-subscription notifyUri cannot be reached. In PfdChangeNotifier.FlushNotifications(), the notifier calls NnefPFDmanagementNotify(...) and on any delivery error invokes logger.PFDManageLog.Fatal(err), which is os.Exit(1)-equivalent in Go. An attacker who can create a PFD subscription with an attacker-chosen notifyUri and then trigger a PFD change can deterministically kill NEF on the asynchronous delivery attempt -- the process exits with status 1, dropping NEF's entire SBI surface until restart. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's BSF PUT /nbsf-management/v1/subscriptions/{subId} handler has an unsynchronized write on the global Subscriptions map. The handler first reads the map under RLock() via BSFContext.GetSubscription(subId), but if the subscription does not exist, ReplaceIndividualSubcription() writes back to the same map directly without taking the mutex (bsfContext.BsfSelf.Subscriptions[subId] = subscription). Under concurrent authenticated PUT load, one goroutine can read while another writes the map, which causes the Go runtime to abort the process with fatal error: concurrent map read and map write (Go runtime panics that come from concurrent map access bypass recover() and terminate the process). The BSF container exits with code 2 -- the entire BSF SBI surface goes down until restart. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-policyauthorization/v1/app-sessions handler panics on a single authenticated request whose ascReqData.suppFeat == "1" (enabling traffic-routing feature negotiation) and whose medComponents entries supply an afAppId but NO AfRoutReq. The create path then calls provisioningOfTrafficRoutingInfo(smPolicy, appID, routeReq, ...) with routeReq == nil and dereferences routeReq.RouteToLocs (and other fields) without a nil check, causing runtime error: invalid memory address or nil pointer dereference. Gin recovery converts the panic into HTTP 500. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's PCF POST /npcf-smpolicycontrol/v1/sm-policies handler (HandleCreateSmPolicyRequest) panics with a nil-pointer dereference when a downstream OpenAPI consumer call (UDR lookup) returns 404 Not Found and the consumer wrapper returns err != nil together with a nil response struct. The handler logs the OpenAPI error and continues executing instead of returning, then dereferences the nil response struct on a subsequent line and panics. Gin recovery converts the panic into HTTP 500, so a single attacker-shaped POST returns 500 instead of a clean 4xx whenever the downstream lookup fails. The PCF process keeps running. The trigger is a single POST containing input that causes the downstream UDR lookup to fail (e.g. an unknown DNN). In 4.2.1 this endpoint is also reachable WITHOUT an Authorization header because the PCF Npcf_SMPolicyControl route group is mounted without inbound auth middleware. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, free5GC's NEF mounts the 3gpp-pfd-management API without inbound OAuth2/bearer-token authorization. A network attacker who can reach NEF on the SBI can create, read, and delete PFD-management transaction state with a forged or arbitrary bearer token (e.g. Authorization: Bearer not-a-real-token). The route group is also reachable even when the running config's ServiceList does not declare it, so operators who think they disabled the service via config are still exposed. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the free5GC UDM component fails to validate the supi path parameter in six GET handlers of the nudm-sdm (Subscriber Data Management) service. An unauthenticated attacker can inject control characters into the SUPI parameter, causing UDM to forward a malformed request to UDR and return a 500 Internal Server Error response that exposes internal infrastructure details. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, PCF Npcf_SMPolicyControl missing authentication middleware allows unauthenticated access to SM policy handlers and disclosure of subscriber SUPI. In NewServer(), the smPolicyGroup route group is created and routes are applied without attaching the router authorization middleware. In contrast, other PCF service groups such as Npcf_PolicyAuthorization do attach RouterAuthorizationCheck before route registration. Because the middleware is missing, requests to the /npcf-smpolicycontrol/v1/sm-policies, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}, /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/update, and /npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/delete endpoints can reach business logic even when no valid OAuth token is provided. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not enforce the concurrent security procedure rules defined in 3GPP TS 33.501 §6.9.5.1. The AMF does not check for ongoing N2 handover procedures before initiating a NAS Security Mode Command, and vice versa. This can lead to mismatches between NAS and AS security contexts in the network and the UE. This vulnerability is fixed in 4.2.2.

free5GC is an open-source implementation of the 5G core network. Prior to 4.2.2, the AMF in Free5GC does not verify the UE Security Capabilities received in NGAP PathSwitchRequest messages against its locally stored values, as mandated by 3GPP TS 33.501 §6.7.3.1. A malicious gNB can overwrite the AMF's stored UE security capabilities with arbitrary values, which are then propagated in PathSwitchRequest Acknowledge messages and subsequent Handover Request messages. This leads to persistent handover denial-of-service for affected UEs. This vulnerability is fixed in 4.2.2.

free5GC AMF provides Access & Mobility Management Function (AMF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. Prior to version 1.4.3, the `HTTPUEContextTransfer` handler in `internal/sbi/api_communication.go` does not include a `default` case in the `Content-Type` switch statement. When a request arrives with an unsupported `Content-Type`, the deserialization step is silently skipped, `err` remains `nil`, and the processor is invoked with a completely uninitialized `UeContextTransferRequest` object. Version 1.4.3 contains a fix.

free5GC UDR is the Policy Control Function (PCF) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. A memory leak vulnerability in versions prior to 1.4.3 allows any unauthenticated attacker with network access to the PCF SBI interface to cause uncontrolled memory growth by sending repeated HTTP requests to the OAM endpoint. The root cause is a `router.Use()` call inside an HTTP handler that registers a new CORS middleware on every incoming request, permanently growing the Gin router's handler chain. This leads to progressive memory exhaustion and eventual Denial of Service of the PCF, preventing all UEs from obtaining AM and SM policies and blocking 5G session establishment. Version 1.4.3 contains a patch.

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.2, a fail-open request handling flaw in the UDR service causes the `/nudr-dr/v2/policy-data/subs-to-notify` POST handler to continue processing requests even after request body retrieval or deserialization errors. This may allow unintended creation of Policy Data notification subscriptions with invalid, empty, or partially processed input, depending on downstream processor behavior. As of time of publication, a patched version is not available.

free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the PUT handler for updating Policy Data notification subscriptions at /nudr-dr/v2/policy-data/subs-to-notify/{subsId} does not return after request body retrieval or deserialization errors. Although HTTP 500 or 400 error responses are sent, execution continues and the processor is invoked with a potentially uninitialized or partially initialized PolicyDataSubscription object. This fail-open behavior may allow unintended modification of existing Policy Data notification subscriptions with invalid or empty input, depending on downstream processor and storage behavior. A patched version was not available at the time of publication.

free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the handler for creating or updating Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is created or overwritten regardless. An unauthenticated attacker with access to the 5G Service Based Interface can create or overwrite arbitrary Traffic Influence Subscriptions, including injecting attacker-controlled notificationUri values and arbitrary SUPIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.

free5GC is an open-source implementation of the 5G core network. In versions 4.2.1 and below of the UDR service, the handler for reading Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription data is returned alongside the 404 response. An unauthenticated attacker with access to the 5G Service Based Interface can read arbitrary Traffic Influence Subscriptions, including SUPIs/IMSIs, DNNs, S-NSSAIs, and callback URIs, by supplying any value for the influenceId path segment. A patched version was not available at the time of publication.

free5GC is an open-source implementation of the 5G core network. In versions 1.4.2 and below of the UDR service, the handler for deleting Traffic Influence Subscriptions checks whether the influenceId path segment equals subs-to-notify, but does not return after sending the HTTP 404 response when validation fails. Execution continues and the subscription is deleted regardless. An unauthenticated attacker with access to the 5G Service Based Interface can delete arbitrary Traffic Influence Subscriptions by supplying any value for the influenceId path segment, while the API misleadingly returns a 404 Not Found response. A patched version was not available at the time of publication.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions 4.2.1 and below contain an information disclosure vulnerability in the UDR (Unified Data Repository) service. The handler for GET /nudr-dr/v2/application-data/influenceData/subs-to-notify sends an HTTP 400 error response when required query parameters are missing but does not return afterward. Execution continues into the processor function, which queries the data repository and appends the full list of Traffic Influence Subscriptions, including SUPI/IMSI values, to the response body. An unauthenticated attacker with network access to the 5G Service Based Interface can retrieve stored subscriber identifiers with a single parameterless HTTP GET request. The SUPI is the most sensitive subscriber identifier in 5G networks, and its exposure undermines the privacy guarantees of the 3GPP SUCI concealment mechanism at the core network level. A similar bypass exists when sending a malformed snssai parameter due to the same missing return pattern.

An issue in Free5GC v.4.2.0 and before allows a remote attacker to cause a denial of service via the function HandleAuthenticationFailure of the component AMF

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. In versions prior to 1.4.2, the UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling PATCH requests with an empty supi path parameter. Additionally, the UDM incorrectly translates the PATCH method to PUT when forwarding to UDR, indicating a deeper architectural issue. This leaks internal error handling behavior, making it difficult for clients to distinguish between client-side errors and server-side failures. The issue has been patched in version 1.4.2.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to null byte injection in URL path parameters. A remote attacker can inject null bytes (URL-encoded as %00) into the supi path parameter of the UDM's Nudm_SubscriberDataManagement API. This causes URL parsing failure in Go's net/url package with the error "invalid control character in URL", resulting in a 500 Internal Server Error. This null byte injection vulnerability can be exploited for denial of service attacks. When the supi parameter contains null characters, the UDM attempts to construct a URL for UDR that includes these control characters. Go's URL parser rejects them, causing the request to fail with 500 instead of properly validating input and returning 400 Bad Request. This issue has been fixed in version 1.4.2.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. In versions prior to 1.4.2, the UDM incorrectly converts a downstream 400 Bad Request (from UDR) into a 500 Internal Server Error when handling DELETE requests with an empty supi path parameter. This leaks internal error handling behavior and makes it difficult for clients to distinguish between client-side errors and server-side failures. When a client sends a DELETE request with an empty supi (e.g., double slashes // in URL path), the UDM forwards the malformed request to UDR, which correctly returns 400. However, UDM propagates this as 500 SYSTEM_FAILURE instead of returning the appropriate 400 error to the client. This violates REST API best practices for DELETE operations. The issue has been patched in version 1.4.2.

Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to procedure panic caused by Nil Pointer Dereference in the /sdm-subscriptions endpoint. A remote attacker can cause the UDM service to panic and crash by sending a crafted POST request to the /sdm-subscriptions endpoint with a malformed URL path containing path traversal sequences (../) and a large JSON payload. The DataChangeNotificationProcedure function in notifier.go attempts to access a nil pointer without proper validation, causing a complete service crash with "runtime error: invalid memory address or nil pointer dereference". Exploitation would result in UDM functionality disruption until recovery by restart. This issue has been fixed in version 1.4.2.

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. All deployments of free5GC using the Nnef_PfdManagement service may be affected. free5gc/udr pull request 56 contains a patch for the issue. There is no direct workaround at the application level. The recommendation is to apply the provided patch.

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, remote attackers can inject control characters (e.g., %00) into the supi parameter, triggering internal URL parsing errors (net/url: invalid control character). This exposes system-level error details and can be used for service fingerprinting. All deployments of free5GC using the UDM Nudm_UEAU service may be affected. free5gc/udm pull request 75 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics and terminates when processing a malformed PFCP SessionReportRequest on the PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics and terminates when processing a malformed PFCP SessionReportRequest on the PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

free5GC SMF provides Session Management Function for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, SMF panics due to nil pointer dereference and the SMF process terminates. This is triggered by a malformed PFCP SessionReportRequest on the SMF PFCP (UDP/8805) interface. No known upstream fix is available, but some workarounds are available. ACL/firewall the PFCP interface so only trusted UPF IPs can reach SMF (reduce spoofing/abuse surface); drop/inspect malformed PFCP SessionReportRequest messages at the network edge where feasible, and/or add recover() around PFCP handler dispatch to avoid whole-process termination (mitigation only).

free5GC is an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 of the User Data Repository are affected by Improper Error Handling with Information Exposure. The NEF component reliably leaks internal parsing error details (e.g., invalid character 'n' after top-level value) to remote clients, which can aid attackers in service fingerprinting. All deployments of free5GC using the Nnef_PfdManagement service may be vulnerable. free5gc/udr pull request 56 contains a patch. No direct workaround is available at the application level. Applying the official patch is recommended.

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 have a NULL Pointer Dereference vulnerability. Remote unauthenticated attackers can trigger a service panic (Denial of Service) by sending a crafted PUT request with an unexpected ueId, crashing the UDM service. All deployments of free5GC using the UDM component may be affected. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, remote attackers can inject control characters (e.g., %00) into the ueId parameter, triggering internal URL parsing errors (net/url: invalid control character). This exposes system implementation details and can aid in service fingerprinting. All deployments of free5GC using the UDM Nudm_UECM service may be affected. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

free5gc UDM provides Unified Data Management (UDM) for free5GC, an open-source project for 5th generation (5G) mobile core networks. In versions up to and including 1.4.1, the service reliably leaks detailed internal error messages (e.g., strconv.ParseInt parsing errors) to remote clients when processing invalid pduSessionId inputs. This exposes implementation details and can be used for service fingerprinting. All deployments of free5GC using the UDM Nudm_UECM DELETE service may be vulnerable. free5gc/udm pull request 76 contains a fix for the issue. No direct workaround is available at the application level. Applying the official patch is recommended.

free5GC is an open-source project for 5th generation (5G) mobile core networks. Versions up to and including 1.4.1 of free5GC's AMF service have a Buffer Overflow vulnerability leading to Denial of Service. Remote unauthenticated attackers can crash the AMF service by sending a specially crafted NAS Registration Request with a malformed 5GS Mobile Identity, causing complete denial of service for the 5G core network. All deployments of free5GC using the AMF component may be affected. Pull request 43 of the free5gc/nas repo contains a fix. No direct workaround is available at the application level. Applying the official patch is recommended.

free5GC go-upf is the User Plane Function (UPF) implementation for 5G networks that is part of the free5GC project. Versions prior to 1.2.8 have a Heap-based Buffer Overflow (CWE-122) vulnerability leading to Denial of Service. Remote attackers can crash the UPF network element by sending a specially crafted PFCP Session Modification Request with an invalid SDF Filter length field. This causes a heap buffer overflow, resulting in complete service disruption for all connected UEs and potential cascading failures affecting the SMF. All deployments of free5GC using the UPF component may be affected. Version 1.2.8 of go-upf contains a fix.

free5GC is an open-source project for 5th generation (5G) mobile core networks. free5GC go-upf versions up to and including 1.2.6, corresponding to free5gc smf up to and including 1.4.0, have an Improper Input Validation and Protocol Compliance vulnerability leading to Denial of Service. Remote attackers can disrupt core network functionality by sending a malformed PFCP Association Setup Request. The UPF incorrectly accepts it, entering an inconsistent state that causes subsequent legitimate requests to trigger SMF reconnection loops and service degradation. All deployments of free5GC using the UPF and SMF components may be affected. As of time of publication, a fix is in development but not yet available. No direct workaround is available at the application level. Applying the official patch, once released, is recommended.

free5GC UDR is the user data repository (UDR) for free5GC, an an open-source project for 5th generation (5G) mobile core networks. Versions prior to 1.4.1 contain an Improper Error Handling vulnerability with Information Exposure. All deployments of free5GC using the Nnef_PfdManagement service may be affected. The NEF component reliably leaks internal parsing errors (e.g., invalid character 'n' after top-level value) to remote clients. This can aid attackers in fingerprinting server software and logic flows. Version 1.4.1 fixes the issue. There is no direct workaround at the application level. The recommended mitigation is to apply the provided patch.

A vulnerability has been found in Free5GC up to 4.1.0. This affects an unknown function of the component PFCP UDP Endpoint. Such manipulation leads to denial of service. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

An improper input validation and protocol compliance vulnerability in free5GC v4.0.1 allows remote attackers to cause a denial of service. The UPF incorrectly accepts a malformed PFCP Association Setup Request, violating 3GPP TS 29.244. This places the UPF in an inconsistent state where a subsequent valid PFCP Session Establishment Request triggers a cascading failure, disrupting the SMF connection and causing service degradation.