CVE-2026-31430 (GCVE-0-2026-31430)
Vulnerability from cvelistv5 – Published: 2026-04-20 09:43 – Updated: 2026-04-20 09:43
VLAI?
Title
X.509: Fix out-of-bounds access when parsing extensions
Summary
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 ?
No CVSS data available.
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Affected:
30eae2b037af54b24109dcaea21db46f6285c69b , < 672b526def1f94c1be8eb11b885b803da0d8c2f1
(git)
Affected: 30eae2b037af54b24109dcaea21db46f6285c69b , < 30ab358fad0c7daa1d282ec48089901b21b36a20 (git) Affected: 30eae2b037af54b24109dcaea21db46f6285c69b , < 206121294b9cf27f0589857f80d64f87e496ffb2 (git) Affected: 30eae2b037af54b24109dcaea21db46f6285c69b , < 7fb4dadc2734f4020d7543d688b8d49c8e569c61 (git) Affected: 30eae2b037af54b24109dcaea21db46f6285c69b , < d702c3408213bb12bd570bb97204d8340d141c51 (git) |
||
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"dateReserved": "2026-03-09T15:48:24.089Z",
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}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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