CyberSecBulletin
CVE-2026-53254NVD status: Modified

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-53254 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions 7c15c7c2878957cbfed93bcc29c13fdace464254, 0d637136ce89f9a2309b2c3502402ce400dab0ef, 98377e6b1a1a56561ec66a181573ea2b61b2079e 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 0.27% 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 7c15c7c2878957cbfed93bcc29c13fdace464254 or 0d637136ce89f9a2309b2c3502402ce400dab0ef or 98377e6b1a1a56561ec66a181573ea2b61b2079e or 1b070ac9e99c2c2c3a8112943ca98ab6fca7f10c, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.15.210 or 6.1.176 or 6.6.143 or 6.12.94, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 7c15c7c2878957cbfed93bcc29c13fdace464254; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 0d637136ce89f9a2309b2c3502402ce400dab0ef; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 98377e6b1a1a56561ec66a181573ea2b61b2079e; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 1b070ac9e99c2c2c3a8112943ca98ab6fca7f10c; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 3eabc6d47a0ad22b053329997aaf0ec1e581e392; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 08b9c1fbe78f4ad3f6250c6541cfaabdbeb81997; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 23882b828c3c8c51d0c946446a396b10abb3b16b; 2.6.127c15c7c2878957cbfed93bcc29c13fdace464254, 0d637136ce89f9a2309b2c3502402ce400dab0ef, 98377e6b1a1a56561ec66a181573ea2b61b2079e, 1b070ac9e99c2c2c3a8112943ca98ab6fca7f10c, 3eabc6d47a0ad22b053329997aaf0ec1e581e392, 08b9c1fbe78f4ad3f6250c6541cfaabdbeb81997
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystemall versionsNot stated
LinuxLinux Kernel2.6.12.1 up to, but not including, 5.15.210; 5.16 up to, but not including, 6.1.176; 6.2 up to, but not including, 6.6.143; 6.7 up to, but not including, 6.12.94; 6.13 up to, but not including, 6.18.36; 6.19 up to, but not including, 7.0.13; 2.6.12; 7.15.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13

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
AdjacentThe attacker must be on the same local network segment.
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:A/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: Bluetooth: RFCOMM: validate skb length in MCC handlers The RFCOMM MCC handlers cast skb->data to protocol-specific structs without validating skb->len first. A malicious remote device can send truncated MCC frames and trigger out-of-bounds reads in these handlers. Fix this by using skb_pull_data() to validate and access the required data before dereferencing it. rfcomm_recv_rpn() requires special handling since ETSI TS 07.10 allows 1-byte RPN requests. Handle this by validating only the DLCI byte first, and validating the full struct only when len > 1.

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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