CVE-2026-64053 (GCVE-0-2026-64053)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:39 – Updated: 2026-08-05 12:38
VLAI
Title
block: don't overwrite bip_vcnt in bio_integrity_copy_user()
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 3991657ae7074c3c497bf095093178bed37ea1b4 , < d18160c9525c63c203656fefd847e94b538cd4a4 (git)
Affected: 3991657ae7074c3c497bf095093178bed37ea1b4 , < 0d48654af4d1390c888389206cc13b51b82c30e6 (git)
Affected: 3991657ae7074c3c497bf095093178bed37ea1b4 , < 066be1439593a381b1a29663becfcfe0c92363e7 (git)
Affected: 3991657ae7074c3c497bf095093178bed37ea1b4 , < 637ad3a56a3b889527d1dacea6fea2a8bd648140 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.11
Unaffected: 0 , < 6.11 (semver)
Unaffected: 6.12.92 , ≤ 6.12.* (semver)
Unaffected: 6.18.34 , ≤ 6.18.* (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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