CVE-2025-38191 (GCVE-0-2025-38191)

Vulnerability from cvelistv5 – Published: 2025-07-04 13:37 – Updated: 2026-08-05 12:00
VLAI
Title
ksmbd: fix null pointer dereference in destroy_previous_session
Summary
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix null pointer dereference in destroy_previous_session If client set ->PreviousSessionId on kerberos session setup stage, NULL pointer dereference error will happen. Since sess->user is not set yet, It can pass the user argument as NULL to destroy_previous_session. sess->user will be set in ksmbd_krb5_authenticate(). So this patch move calling destroy_previous_session() after ksmbd_krb5_authenticate().
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 281afc52e2961cd5dd8326ebc9c5bc40904c0468 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 0902625a24eea7fdc187faa5d97df244d159dd6e (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 1193486dffb7432a09f57f5d09049b4d4123538b (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 076f1adefb9837977af7ed233883842ddc446644 (git)
Affected: 0626e6641f6b467447c81dd7678a69c66f7746cf , < 7ac5b66acafcc9292fb935d7e03790f2b8b2dc0e (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.1.142 , ≤ 6.1.* (semver)
Unaffected: 6.6.95 , ≤ 6.6.* (semver)
Unaffected: 6.12.35 , ≤ 6.12.* (semver)
Unaffected: 6.15.4 , ≤ 6.15.* (semver)
Unaffected: 6.16 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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}



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  • 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.


Detection rules are retrieved from Rulezet.


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.