CVE-2026-72423 (GCVE-0-2026-72423)
Vulnerability from cvelistv5
Published
2026-08-15 05:56
Modified
2026-10-30 12:29
Severity ?
8.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Guard conntrack opts error writes The conntrack lookup and allocation kfuncs take an opts pointer together with an opts__sz argument. The verifier checks only the memory range described by opts__sz, but the wrappers unconditionally write opts->error whenever the internal lookup or allocation helper returns an error. For an invalid size smaller than the end of opts->error, that write can land outside the verifier-checked range. Keep returning NULL for invalid arguments, but only report the error through opts->error when the supplied size includes the field. This preserves error reporting for the supported 12-byte and 16-byte layouts, and for other invalid sizes that still include opts->error.
References
Impacted products
Vendor Product Version
Linux Linux Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
Version: b4c2b9593a1c4c3a718370e34af28e817fd5e5c6
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