HOMEVULNERABILITIESCVE-2020-27836
CRITICAL

CVE-2020-27836

CWE-732Published: August 22, 2022· Updated: Jun 17, 2026

9.8
CVSS v3.1

Official Description

A flaw was found in cluster-ingress-operator. A change to how the router-default service allows only certain IP source ranges could allow an attacker to access resources that would otherwise be restricted to specified IP ranges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability..

NVD Source

Risk Analysis

A flaw in the cluster-ingress-operator allows attackers to bypass IP source range restrictions on the router-default service. This enables unauthorized access to restricted resources, presenting a critical risk to system security and availability.

This vulnerability is remotely exploitable with low complexity, but there is no known public exploit and it is not in the KEV catalog.

Recommended Action

Apply the latest security patches for Red Hat OpenShift Container Platform and Enterprise Linux to remediate the ingress configuration flaw.

Generated by the CTIWATCH analysis pipeline from this CVE's metadata (CVSS, EPSS, KEV status, exploit intelligence). Verify against vendor advisories before acting.

Technical Analysis

CVE-2020-27836 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

Red Hat2 product(s)
openshift container platformenterprise linux
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1906267
PATCHhttps://github.com/openshift/cluster-ingress-operator/pull/507/commits/92c83f281ba5fb6a1d91ecc3beaa4bcf2647a729
PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1906267
PATCHhttps://github.com/openshift/cluster-ingress-operator/pull/507/commits/92c83f281ba5fb6a1d91ecc3beaa4bcf2647a729
ADVISORYhttps://access.redhat.com/security/cve/CVE-2020-27836
ADVISORYhttps://bugzilla.redhat.com/show_bug.cgi?id=1905490
ADVISORYhttps://access.redhat.com/security/cve/CVE-2020-27836
ADVISORYhttps://bugzilla.redhat.com/show_bug.cgi?id=1905490

All References (8)

→
https://access.redhat.com/security/cve/CVE-2020-27836Vendor Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=1905490Issue Tracking · Permissions Required · Vendor Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=1906267Issue Tracking · Patch · Vendor Advisory
→
https://github.com/openshift/cluster-ingress-operator/pull/507/commits/92c83f281ba5fb6a1d91ecc3beaa4bcf2647a729Patch · Third Party Advisory
→
https://access.redhat.com/security/cve/CVE-2020-27836Vendor Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=1905490Issue Tracking · Permissions Required · Vendor Advisory
→
https://bugzilla.redhat.com/show_bug.cgi?id=1906267Issue Tracking · Patch · Vendor Advisory
→
https://github.com/openshift/cluster-ingress-operator/pull/507/commits/92c83f281ba5fb6a1d91ecc3beaa4bcf2647a729Patch · Third Party Advisory

Quick Facts

CVE IDCVE-2020-27836
CVSS Score9.8 / 10
SeverityCRITICAL
WeaknessCWE-732
CISA KEVNo
Affected1 vendor(s)
PublishedAug 22, 2022

Related CVEs (CWE-732)

CVE-2026-9508
10.0
CVE-2025-14988
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CVE-2025-12004
10.0
CVE-2014-125121
10.0
CVE-2025-69426
10.0
CVE-2023-40622
9.9

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2020-27836 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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