CyberSecBulletin
CVE-2026-31614NVD status: Analyzed

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-31614 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 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 bfbc74df8bbe095b3ed68f6d4487b368af087890, 5cc0574c84aa73946ade587c41e81757b8b01cb5, b2b76d09a64c538c57006180103fc1841e8cfa66 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 0.13% 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 bfbc74df8bbe095b3ed68f6d4487b368af087890 or 5cc0574c84aa73946ade587c41e81757b8b01cb5 or b2b76d09a64c538c57006180103fc1841e8cfa66 or ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.6.136 or 6.12.83 or 6.18.24 or 6.19.14, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux7449d736bbbd160c76b01b8fcdf72f58a8757d4b up to, but not including, bfbc74df8bbe095b3ed68f6d4487b368af087890; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, 5cc0574c84aa73946ade587c41e81757b8b01cb5; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, b2b76d09a64c538c57006180103fc1841e8cfa66; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, a893f1757d9a4009e4a8d7ceb2312142fe29cea4; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, 3d8b9d06bd3ac4c6846f5498800b0f5f8062e53b; 6.6.32 up to, but not including, 6.6.136; 6.9bfbc74df8bbe095b3ed68f6d4487b368af087890, 5cc0574c84aa73946ade587c41e81757b8b01cb5, b2b76d09a64c538c57006180103fc1841e8cfa66, ba3ad159aa61810bbe0acaf39578b1ebfb6f1a18, a893f1757d9a4009e4a8d7ceb2312142fe29cea4, 3d8b9d06bd3ac4c6846f5498800b0f5f8062e53b
LinuxLinux Kernel6.6.32 up to, but not including, 6.6.136; 6.9 up to, but not including, 6.12.83; 6.13 up to, but not including, 6.18.24; 6.19 up to, but not including, 6.19.14; 7.0 up to, but not including, 7.0.16.6.136, 6.12.83, 6.18.24, 6.19.14, 7.0.1

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
NoneNothing can be modified.
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:N/A:H. Scored by NVD.

Official description

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix off-by-8 bounds check in check_wsl_eas() The bounds check uses (u8 *)ea + nlen + 1 + vlen as the end of the EA name and value, but ea_data sits at offset sizeof(struct smb2_file_full_ea_info) = 8 from ea, not at offset 0. The strncmp() later reads ea->ea_data[0..nlen-1] and the value bytes follow at ea_data[nlen+1..nlen+vlen], so the actual end is ea->ea_data + nlen + 1 + vlen. Isn't pointer math fun? The earlier check (u8 *)ea > end - sizeof(*ea) only guarantees the 8-byte header is in bounds, but since the last EA is placed within 8 bytes of the end of the response, the name and value bytes are read past the end of iov. Fix this mess all up by using ea->ea_data as the base for the bounds check. An "untrusted" server can use this to leak up to 8 bytes of kernel heap into the EA name comparison and influence which WSL xattr the data is interpreted as.

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: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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