CVE-2026-53076: Linux Kernel

High severity, CVSS 7.1. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix OOB in pcpu_init_value An out-of-bounds read occurs when copying element from a BPF_MAP_TYPE_CGROUP_STORAGE map to another pcpu map with the same value_size that is not rounded up to 8 bytes. The issue happens when: 1. A CGROUP_STORAGE map is created with value_size not aligned to 8 bytes (e.g., 4 bytes) 2. A pcpu map is created with the same value_size (e.g., 4 bytes) 3. Update element in 2 with data in 1 pcpu_init_value assumes that all sources are rounded up to 8 bytes, and invokes copy_map_value_long to make a data copy, However, the assumption doesn't stand since there are some cases where the source may not be rounded up to 8 bytes, e.g., CGROUP_STORAGE, skb->data. the verifier verifies exactly the size that the source claims, not the size rounded up to 8 bytes by kernel, an OOB happens when the source has only 4 bytes while the copy size(4) is rounded up to 8.

Affected products

• Linux Linux Kernel: from 5.4.78, before 5.5 (fixed in 5.5); from 5.9.9, before 5.10 (fixed in 5.10); from 5.10.1, before 6.6.141 (fixed in 6.6.141); from 6.7, before 6.12.91 (fixed in 6.12.91); from 6.13, before 6.18.33 (fixed in 6.18.33); from 6.19, before 7.0.10 (fixed in 7.0.10); …

Published 2026-06-24. Last modified 2026-07-21.