CVE-2025-39822 (GCVE-0-2025-39822)

Vulnerability from cvelistv5 – Published: 2025-09-16 13:00 – Updated: 2026-05-11 21:37
VLAI
Title
io_uring/kbuf: fix signedness in this_len calculation
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: fix signedness in this_len calculation When importing and using buffers, buf->len is considered unsigned. However, buf->len is converted to signed int when committing. This can lead to unexpected behavior if the buffer is large enough to be interpreted as a negative value. Make min_t calculation unsigned.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-14 18:17 UTC
CWE
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6639 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: cf9536e550dd243a1681fdbf804221527da20a80 , < f4f411c068402c370c4f9a9d4950a97af97bbbb1 (git)
Affected: cf9536e550dd243a1681fdbf804221527da20a80 , < c64eff368ac676e8540344d27a3de47e0ad90d21 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.15
Unaffected: 0 , < 6.15 (semver)
Unaffected: 6.16.5 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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