CVE-2026-72423

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxb4c2b9593a1c4c3a718370e34af28e817fd5e5c6 < dd74c80203842a21b2ebb9f70d1260d9aa20fa05affected
LinuxLinuxb4c2b9593a1c4c3a718370e34af28e817fd5e5c6 < 6f6183a39533d727deaa5061cadae6dd9e6744d0affected
LinuxLinux5.18affected
LinuxLinux0 < 5.18unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References