CVE-2026-43366 (GCVE-0-2026-43366)
Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-08-05 12:27
VLAI
EPSS
VEX
Title
io_uring/kbuf: check if target buffer list is still legacy on recycle
Summary
In the Linux kernel, the following vulnerability has been resolved:
io_uring/kbuf: check if target buffer list is still legacy on recycle
There's a gap between when the buffer was grabbed and when it
potentially gets recycled, where if the list is empty, someone could've
upgraded it to a ring provided type. This can happen if the request
is forced via io-wq. The legacy recycling is missing checking if the
buffer_list still exists, and if it's of the correct type. Add those
checks.
Severity
7.8 (High)
Assigner
References
6 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < a7b33671e418fca507feebd1d56e7f4952a4b25c
(git)
Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 439a6728ec4641ffad1ca796622c19bc525e570f (git) Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < f3fb54e7a8b4aadcc2836ee463eec8c88709b8aa (git) Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 50ad880db3013c6fee0ef13781762a39e2e7ef83 (git) Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < 97b57f69fee1b61b41acbf37e7720cac9d389fa4 (git) Affected: c7fb19428d67dd0a2a78a4f237af01d39c78dc5a , < c2c185be5c85d37215397c8e8781abf0a69bec1f (git) |
guessed | |
| Linux | Linux |
Affected:
5.19
Unaffected: 0 , < 5.19 (semver) Unaffected: 6.1.167 , ≤ 6.1.* (semver) Unaffected: 6.6.130 , ≤ 6.6.* (semver) Unaffected: 6.12.78 , ≤ 6.12.* (semver) Unaffected: 6.18.19 , ≤ 6.18.* (semver) Unaffected: 6.19.9 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix) |
guessed |
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}
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"current_release_date": "2026-07-02T12:46:36+00:00",
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"id": "CVE-2026-43366",
"initial_release_date": "2026-05-08T00:00:00+00:00",
"product_status:known_affected": "184",
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"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: io_uring/kbuf: check if target buffer list is still legacy on recycle",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43366.json",
"version": "3"
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}
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