CVE-2026-31430 (GCVE-0-2026-31430)
Vulnerability from cvelistv5
Published
2026-04-20 09:43
Modified
2026-04-20 09:43
Severity ?
VLAI Severity ?
EPSS score ?
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.
References
Impacted products
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"providerMetadata": {
"dateUpdated": "2026-04-20T09:43:03.919Z",
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"title": "X.509: Fix out-of-bounds access when parsing extensions",
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"cveId": "CVE-2026-31430",
"datePublished": "2026-04-20T09:43:03.919Z",
"dateReserved": "2026-03-09T15:48:24.089Z",
"dateUpdated": "2026-04-20T09:43:03.919Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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