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.

A flaw was found in the Linux kernel's Berkeley Packet Filter (BPF) verifier. This vulnerability occurs because the BPF verifier incorrectly handles dynamic inner array lookups in ARRAY_OF_MAPS. When an inner map template is replaced by a concrete inner array with a different maximum entry size, the verifier may perform incorrect bounds checking. A local attacker could exploit this flaw by creating a specially crafted BPF program, potentially leading to out-of-bounds memory access. This could result in a denial of service or, in some cases, privilege escalation.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt Red Hat Hardened Images Not affected erlang27 https://www.cve.org/CVERecord?id=CVE-2026-64353 https://nvd.nist.gov/vuln/detail/CVE-2026-64353 https://lore.kernel.org/linux-cve-announce/2026072519-CVE-2026-64353-6baf@gregkh/T