CVE-2025-39963 (GCVE-0-2025-39963)
Vulnerability from cvelistv5 – Published: 2025-10-09 12:13 – Updated: 2026-10-15 22:02
VLAI
EPSS
VEX
Title
io_uring: fix incorrect io_kiocb reference in io_link_skb
Summary
In the Linux kernel, the following vulnerability has been resolved:
io_uring: fix incorrect io_kiocb reference in io_link_skb
In io_link_skb function, there is a bug where prev_notif is incorrectly
assigned using 'nd' instead of 'prev_nd'. This causes the context
validation check to compare the current notification with itself instead
of comparing it with the previous notification.
Fix by using the correct prev_nd parameter when obtaining prev_notif.
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 21:55 UTC
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
6fe4220912d19152a26ce19713ab232f4263018d , < a89c34babc2e5834aa0905278f26f4dbe4b26b76
(git)
Affected: 6fe4220912d19152a26ce19713ab232f4263018d , < 50a98ce1ea694f1ff8e87bc2f8f84096d1736f6a (git) Affected: 6fe4220912d19152a26ce19713ab232f4263018d , < 2c139a47eff8de24e3350dadb4c9d5e3426db826 (git) |
guessed | |
| Linux | Linux |
Affected:
6.10
Unaffected: 0 , < 6.10 (semver) Unaffected: 6.12.49 , ≤ 6.12.* (semver) Unaffected: 6.16.9 , ≤ 6.16.* (semver) Unaffected: 6.17 , ≤ * (original_commit_for_fix) |
guessed |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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