CVE-2026-31430
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.08%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.1 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.08% probability · 0th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/206121294b9cf27f0589857f80d64f87e496ffb2Patch
- https://git.kernel.org/stable/c/30ab358fad0c7daa1d282ec48089901b21b36a20Patch
- https://git.kernel.org/stable/c/672b526def1f94c1be8eb11b885b803da0d8c2f1Patch
- https://git.kernel.org/stable/c/7fb4dadc2734f4020d7543d688b8d49c8e569c61Patch
- https://git.kernel.org/stable/c/d702c3408213bb12bd570bb97204d8340d141c51Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.