Riskcovery

CVE-2026-31430

X.509: Fix out-of-bounds access when parsing extensions

State
Published
Severity
Not scored
Published
Apr 20, 2026
Updated
May 11, 2026
Reserved
Mar 9, 2026

Read the record on cve.org

Description

In the Linux kernel, the following vulnerability has been resolved:

X.509: Fix out-of-bounds access when parsing extensions

Leo reports an out-of-bounds access when parsing a certificate with empty Basic Constraints or Key Usage extension because the first byte of the extension is read before checking its length. Fix it.

The bug can be triggered by an unprivileged user by submitting a specially crafted certificate to the kernel through the keyrings(7) API. Leo has demonstrated this with a proof-of-concept program responsibly disclosed off-list.

Scores

The record has no CVSS score.

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 30eae2b037af54b24109dcaea21db46f6285c69b to before 672b526def1f94c1be8eb11b885b803da0d8c2f1Affected
  • 30eae2b037af54b24109dcaea21db46f6285c69b to before 30ab358fad0c7daa1d282ec48089901b21b36a20Affected
  • 30eae2b037af54b24109dcaea21db46f6285c69b to before 206121294b9cf27f0589857f80d64f87e496ffb2Affected
  • 30eae2b037af54b24109dcaea21db46f6285c69b to before 7fb4dadc2734f4020d7543d688b8d49c8e569c61Affected
  • 30eae2b037af54b24109dcaea21db46f6285c69b to before d702c3408213bb12bd570bb97204d8340d141c51Affected
LinuxLinux
  • 6.4Affected
  • before 6.4Not affected
  • 6.6.135 through 6.6.*Not affected
  • 6.12.82 through 6.12.*Not affected
  • 6.18.23 through 6.18.*Not affected
  • 6.19.13 through 6.19.*Not affected
  • 7.0 and laterNot affected

References

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