CVE-2026-64353: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: bpf: Keep dynamic inner array lookups nullable An ARRAY_OF_MAPS can use an array created with BPF_F_INNER_MAP as its inner map template. A concrete inner array with a different max_entries value can then replace the template. After a successful outer map lookup, the verifier represents the resulting map pointer using the inner map template. Const-key lookup nullness elision consequently uses the template max_entries even though the runtime helper uses the concrete inner map max_entries. Do not elide lookup result nullness for maps marked with BPF_F_INNER_MAP, because the template max_entries does not prove that the key is in bounds for the concrete runtime map.

Affected products

• Linux Linux Kernel: from 6.14, before 6.18.40 (fixed in 6.18.40); from 6.19, before 7.1.4 (fixed in 7.1.4)

Published 2026-07-25. Last modified 2026-09-03.