VULNERABILITY INTELLIGENCE
CVE-2026-64053
CVSS score7.8 HIGH
EPSS probability0.13%
CISA KEVNot currently listed
Published2026-07-19
Last modified2026-10-19
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
In the Linux kernel, the following vulnerability has been resolved: block: don't overwrite bip_vcnt in bio_integrity_copy_user() bio_integrity_add_page() already sets bip_vcnt to 1 for the bounce segment. Overwriting it with nr_vecs breaks bip_vcnt <= bip_max_vcnt on WRITE (bip_max_vcnt is 1), so the gap-merge checks in block/blk.h read past the bip_vec[] flex array. On READ the read is in bounds but lands on a saved user bvec instead of the bounce. The line was added for split propagation, but bio_integrity_clone() doesn't copy bip_vcnt and BIP_CLONE_FLAGS excludes BIP_COPY_USER.
Weakness classification
- nvd@nist.gov: NVD-CWE-noinfo
- 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-125