CyberSecBulletin
CVE-2026-31405NVD status: Analyzed

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-31405 is a critical-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 9.8 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 e51238718217c4abdb3ccc3b0c0cde265c7ec629, b2bd2ee73b697c177157bba534e1b1064c2e66a0, 29ef43ceb121d67b87f4cbb08439e4e9e732eff8 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 0.56% 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 e51238718217c4abdb3ccc3b0c0cde265c7ec629 or b2bd2ee73b697c177157bba534e1b1064c2e66a0 or 29ef43ceb121d67b87f4cbb08439e4e9e732eff8 or 1a6da3dbb9985d00743073a1cc1f96e59f5abc30, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.253 or 5.15.203 or 6.1.167 or 6.6.130, 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
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, e51238718217c4abdb3ccc3b0c0cde265c7ec629; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, b2bd2ee73b697c177157bba534e1b1064c2e66a0; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 29ef43ceb121d67b87f4cbb08439e4e9e732eff8; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 1a6da3dbb9985d00743073a1cc1f96e59f5abc30; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 145e50c2c700fa52b840df7bab206043997dd18e; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 8bde543d2a5f935ba2a6a6325a2e02f8a9256fbe; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, f2b65dcb78c8990e4c68a906627433be1fe38a92; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 24d87712727a5017ad142d63940589a36cd25647; and 1 more rangese51238718217c4abdb3ccc3b0c0cde265c7ec629, b2bd2ee73b697c177157bba534e1b1064c2e66a0, 29ef43ceb121d67b87f4cbb08439e4e9e732eff8, 1a6da3dbb9985d00743073a1cc1f96e59f5abc30, 145e50c2c700fa52b840df7bab206043997dd18e, 8bde543d2a5f935ba2a6a6325a2e02f8a9256fbe
LinuxLinux Kernel2.6.12.1 up to, but not including, 5.10.253; 5.11 up to, but not including, 5.15.203; 5.16 up to, but not including, 6.1.167; 6.2 up to, but not including, 6.6.130; 6.7 up to, but not including, 6.12.78; 6.13 up to, but not including, 6.18.19; 6.19 up to, but not including, 6.19.9; 2.6.12; and 1 more ranges5.10.253, 5.15.203, 6.1.167, 6.6.130, 6.12.78, 6.18.19

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
HighData or code can be modified at will.
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:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: media: dvb-net: fix OOB access in ULE extension header tables The ule_mandatory_ext_handlers[] and ule_optional_ext_handlers[] tables in handle_one_ule_extension() are declared with 255 elements (valid indices 0-254), but the index htype is derived from network-controlled data as (ule_sndu_type & 0x00FF), giving a range of 0-255. When htype equals 255, an out-of-bounds read occurs on the function pointer table, and the OOB value may be called as a function pointer. Add a bounds check on htype against the array size before either table is accessed. Out-of-range values now cause the SNDU to be discarded.

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

References

Recent Out-of-bounds Read vulnerabilities

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