CVE-2026-43376 (GCVE-0-2026-43376)
Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-08-05 12:27
VLAI
EPSS
VEX
Title
ksmbd: fix use-after-free by using call_rcu() for oplock_info
Summary
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free by using call_rcu() for oplock_info
ksmbd currently frees oplock_info immediately using kfree(), even
though it is accessed under RCU read-side critical sections in places
like opinfo_get() and proc_show_files().
Since there is no RCU grace period delay between nullifying the pointer
and freeing the memory, a reader can still access oplock_info
structure after it has been freed. This can leads to a use-after-free
especially in opinfo_get() where atomic_inc_not_zero() is called on
already freed memory.
Fix this by switching to deferred freeing using call_rcu().
Severity
9.8 (Critical)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
296cb5457cc6f4a754c4ae29855f8a253d52bcc6 , < 302fef75512b2c8329a3f5efab1ae7ba2562387a
(git)
Affected: d54ab1520d43e95f9b2e22d7a05fc9614192e5a5 , < 08aa9f3c8cf4d0bee44df540dfe34e8d64069f2c (git) Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < 1d6abf145615dbfe267ce3b0a271f95e3780e18e (git) Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < ce8507ee82c888126d8e7565e27c016308d24cde (git) Affected: 18b4fac5ef17f77fed9417d22210ceafd6525fc7 , < 1dfd062caa165ec9d7ee0823087930f3ab8a6294 (git) Affected: d73686367ad68534257cd88a36ca3c52cb8b81d8 (git) Affected: 6.6.88 , < 6.6.130 (semver) Affected: 6.12.25 , < 6.12.78 (semver) Affected: 6.14.4 , < 6.15 (semver) |
guessed | |
| Linux | Linux |
Affected:
6.15
Unaffected: 0 , < 6.15 (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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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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