CVE-2025-39822 (GCVE-0-2025-39822)
Vulnerability from cvelistv5 – Published: 2025-09-16 13:00 – Updated: 2026-05-11 21:37
VLAI
EPSS
VEX
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)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-14 18:17 UTC
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
cf9536e550dd243a1681fdbf804221527da20a80 , < f4f411c068402c370c4f9a9d4950a97af97bbbb1
(git)
Affected: cf9536e550dd243a1681fdbf804221527da20a80 , < c64eff368ac676e8540344d27a3de47e0ad90d21 (git) |
guessed | |
| 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 |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- 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.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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