CVE-2026-31430
Analyzed
Analyzed - Analysis Complete
Out-of-Bounds Access in Linux Kernel X.509 Extension Parsing
Publication date: 2026-04-20
Last updated on: 2026-05-21
Assigner: kernel.org
Description
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 Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | 7.0 |
| linux | linux_kernel | From 6.13 (inc) to 6.18.23 (exc) |
| linux | linux_kernel | From 6.19 (inc) to 6.19.13 (exc) |
| linux | linux_kernel | From 6.7 (inc) to 6.12.82 (exc) |
| linux | linux_kernel | From 6.4 (inc) to 6.6.135 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-125 | The product reads data past the end, or before the beginning, of the intended buffer. |