CyberSecBulletin
CVE-2026-46155NVD status: Modified

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-46155 is a critical-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions dffb44b2e06a2908e249f0f93156fc987eee1d1c, 9b3af35645ff9cd334edc130249f9a2fb2bea25f, 512d33bc8ea4ea5c19728ee118715f4b1f4d1926 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 0.48% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Linux to dffb44b2e06a2908e249f0f93156fc987eee1d1c or 9b3af35645ff9cd334edc130249f9a2fb2bea25f or 512d33bc8ea4ea5c19728ee118715f4b1f4d1926 or a16f70a71be4b5a4eccf39a9bf09b47285f4cb7c, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 6.6.140 or 6.12.88 or 6.18.30 or 7.0.7, whichever matches your release line, or a later version.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux7449d736bbbd160c76b01b8fcdf72f58a8757d4b up to, but not including, dffb44b2e06a2908e249f0f93156fc987eee1d1c; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, 9b3af35645ff9cd334edc130249f9a2fb2bea25f; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, 512d33bc8ea4ea5c19728ee118715f4b1f4d1926; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, a16f70a71be4b5a4eccf39a9bf09b47285f4cb7c; ea41367b2a602f602ea6594fc4a310520dcc64f4 up to, but not including, 8d09328dfda089675e4c049f3f256064a1d1996b; 6.6.32 up to, but not including, 6.6.140; 6.9dffb44b2e06a2908e249f0f93156fc987eee1d1c, 9b3af35645ff9cd334edc130249f9a2fb2bea25f, 512d33bc8ea4ea5c19728ee118715f4b1f4d1926, a16f70a71be4b5a4eccf39a9bf09b47285f4cb7c, 8d09328dfda089675e4c049f3f256064a1d1996b, 6.6.140
LinuxLinux Kernel6.6.32 up to, but not including, 6.6.140; 6.9 up to, but not including, 6.12.88; 6.13 up to, but not including, 6.18.30; 6.19 up to, but not including, 7.0.7; 7.16.6.140, 6.12.88, 6.18.30, 7.0.7

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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
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:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix out-of-bounds read in smb2_compound_op() If a server sends a truncated response but a large OutputBufferLength, and terminates the EA list early, check_wsl_eas() returns success without validating that the entire OutputBufferLength fits within iov_len. Then smb2_compound_op() does: memcpy(idata->wsl.eas, data[0], size[0]); Where size[0] is OutputBufferLength. If iov_len is smaller than size[0], memcpy can read beyond the end of the rsp_iov allocation and leak adjacent kernel heap memory.

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: yes, 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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