CVE-2026-31430
Full vulnerability record from the local CVENow database.
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.
Severity
HIGH
CVSS score
7.1
(v3.1)
Vulnerability status
Analyzed
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-20 10:16:16.877000
Last modified
2026-11-05 22:18:31.233000
View original CVE JSON
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"published": "2026-04-20T10:16:16.877",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nX.509: Fix out-of-bounds access when parsing extensions\n\nLeo reports an out-of-bounds access when parsing a certificate with\nempty Basic Constraints or Key Usage extension because the first byte of\nthe extension is read before checking its length. Fix it.\n\nThe bug can be triggered by an unprivileged user by submitting a\nspecially crafted certificate to the kernel through the keyrings(7) API.\nLeo has demonstrated this with a proof-of-concept program responsibly\ndisclosed off-list."
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