CVE-2026-72423

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.

Package Linux Kernel
Published 2026-08-15
Last modified 2026-08-15
Patch available
Yes

Affected versions

Linux kernel versions 5.18 and later are affected. Fixed in 7.1.5, 7.2-rc1 and their respective stable series.

Affected from
≥ 5.18
Fixed in
✓ 7.1.5 7.1.x ✓ 7.2-rc1

Frequently asked questions

  • What is CVE-2026-72423?

    CVE-2026-72423 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.18 onward and has been patched in 7.1.5 and 7.2-rc1. CVE-2026-72423 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2026-72423?

    Yes. CVE-2026-72423 has been patched. Fixed versions include 7.1.5 and 7.2-rc1. If you are running Linux kernel 5.18 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-72423 actively exploited?

    No. CVE-2026-72423 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.