CyberSecBulletin
CVE-2026-31675NVD status: Modified

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-31675 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 8d3de49c22ec0ec8f7199cc7e2b0559de7306f87, a14b56863348686dd0387eea8ce66b85cf455908, 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.16% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to 8d3de49c22ec0ec8f7199cc7e2b0559de7306f87 or a14b56863348686dd0387eea8ce66b85cf455908 or 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f or 3a2999704ac36cfb4041fed3652d26a3373e8d12, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.6.134 or 6.12.81 or 6.18.22 or 6.19.12, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxc865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, 8d3de49c22ec0ec8f7199cc7e2b0559de7306f87; c865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, a14b56863348686dd0387eea8ce66b85cf455908; c865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f; c865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, 3a2999704ac36cfb4041fed3652d26a3373e8d12; c865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, 4fd258e281fa8bc15e9ce2c7691941537e9258ad; c865e5d99e25a171e8262fc0f7ba608568633c64 up to, but not including, d64cb81dcbd54927515a7f65e5e24affdc73c14b; 2.6.168d3de49c22ec0ec8f7199cc7e2b0559de7306f87, a14b56863348686dd0387eea8ce66b85cf455908, 13a66ca1e235d4bcd53d12d4c68490cad7f8e46f, 3a2999704ac36cfb4041fed3652d26a3373e8d12, 4fd258e281fa8bc15e9ce2c7691941537e9258ad, d64cb81dcbd54927515a7f65e5e24affdc73c14b
LinuxLinux Kernel2.6.16 up to, but not including, 6.6.134; 6.7 up to, but not including, 6.12.81; 6.13 up to, but not including, 6.18.22; 6.19 up to, but not including, 6.19.12; 7.06.6.134, 6.12.81, 6.18.22, 6.19.12

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_netem: fix out-of-bounds access in packet corruption In netem_enqueue(), the packet corruption logic uses get_random_u32_below(skb_headlen(skb)) to select an index for modifying skb->data. When an AF_PACKET TX_RING sends fully non-linear packets over an IPIP tunnel, skb_headlen(skb) evaluates to 0. Passing 0 to get_random_u32_below() takes the variable-ceil slow path which returns an unconstrained 32-bit random integer. Using this unconstrained value as an offset into skb->data results in an out-of-bounds memory access. Fix this by verifying skb_headlen(skb) is non-zero before attempting to corrupt the linear data area. Fully non-linear packets will silently bypass the corruption logic.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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