HOMEVULNERABILITIESCVE-2026-31623
MEDIUM

CVE-2026-31623

Published: April 24, 2026· Updated: Apr 28, 2026

5.5
CVSS v3.1
EPSS:0.02%probability of exploitation in 30 daysPercentile:4.8th

Official Description

In the Linux kernel, the following vulnerability has been resolved:

net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()

A malicious USB device claiming to be a CDC Phonet modem can overflow

the skb_shared_info->frags[] array by sending an unbounded sequence of

full-page bulk transfers.

Drop the skb and increment the length error when the frag limit is

reached. This matches the same fix that commit f0813bcd2d9d ("net:

wwan: t7xx: fix potential skb->frags overflow in RX path") did for the

t7xx driver.

NVD Source

Technical Analysis

CVE-2026-31623 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 5.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

Linux1 product
linux kernel
Source: NVD CPE · 1 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://git.kernel.org/stable/c/600dc40554dc5ad1e6f3af51f700228033f43ea7
PATCHhttps://git.kernel.org/stable/c/9989938d13cc5ba8447eeed5a61acfcf61bc6801
PATCHhttps://git.kernel.org/stable/c/a23b1b1aaf41e174181d5853a70e65d4d01e648c
PATCHhttps://git.kernel.org/stable/c/c183d5775129a0a7495bd61a6e57ec230dcf01e5
PATCHhttps://git.kernel.org/stable/c/d4e1946bea8d6441835eb3fd09b19237ba366a6f
PATCHhttps://git.kernel.org/stable/c/ebf75c6301c4972a87542ebf2d994c6391eb5d46

All References (6)

→
https://git.kernel.org/stable/c/600dc40554dc5ad1e6f3af51f700228033f43ea7Patch
→
https://git.kernel.org/stable/c/9989938d13cc5ba8447eeed5a61acfcf61bc6801Patch
→
https://git.kernel.org/stable/c/a23b1b1aaf41e174181d5853a70e65d4d01e648cPatch
→
https://git.kernel.org/stable/c/c183d5775129a0a7495bd61a6e57ec230dcf01e5Patch
→
https://git.kernel.org/stable/c/d4e1946bea8d6441835eb3fd09b19237ba366a6fPatch
→
https://git.kernel.org/stable/c/ebf75c6301c4972a87542ebf2d994c6391eb5d46Patch

Quick Facts

CVE IDCVE-2026-31623
CVSS Score5.5 / 10
SeverityMEDIUM
CISA KEVNo
EPSS (30d)0.02%
Affected1 vendor
PublishedApr 24, 2026

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2026-31623 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.COM. CVE data is provided under the NVD usage policy.
← All Vulnerabilities·Search for CVE-2026-31623·NVD