Out-of-bounds read in Linux kernel - CVE-2026-64053

Vulnerability details

The vulnerability allows a local user to cause an out-of-bounds read.

The vulnerability exists due to an out-of-bounds read in bio_integrity_copy_user() and the block layer integrity handling when processing bio integrity metadata during read or write operations. A local user can trigger the vulnerable code path to cause an out-of-bounds read.

The issue occurs because bip_vcnt can exceed bip_max_vcnt, causing gap-merge checks to read past the bip_vec[] flexible array; on read operations the access remains in bounds but reaches a saved user bvec instead of the bounce segment.

Affected software

How to mitigate CVE-2026-64053

External References

• https://git.kernel.org/stable/c/066be1439593a381b1a29663becfcfe0c92363e7
• https://git.kernel.org/stable/c/0d48654af4d1390c888389206cc13b51b82c30e6
• https://git.kernel.org/stable/c/637ad3a56a3b889527d1dacea6fea2a8bd648140
• https://git.kernel.org/stable/c/d18160c9525c63c203656fefd847e94b538cd4a4

Related Security Bulletins

• Out-of-bounds read in Linux kernel block
• Ubuntu update for linux-ibm
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Ubuntu update for linux-nvidia-bos
• Ubuntu update for linux-nvidia