CVE-2025-39819 (GCVE-0-2025-39819)

Vulnerability from cvelistv5 – Published: 2025-09-16 13:00 – Updated: 2026-05-12 12:07
VLAI
Title
fs/smb: Fix inconsistent refcnt update
Summary
In the Linux kernel, the following vulnerability has been resolved: fs/smb: Fix inconsistent refcnt update A possible inconsistent update of refcount was identified in `smb2_compound_op`. Such inconsistent update could lead to possible resource leaks. Why it is a possible bug: 1. In the comment section of the function, it clearly states that the reference to `cfile` should be dropped after calling this function. 2. Every control flow path would check and drop the reference to `cfile`, except the patched one. 3. Existing callers would not handle refcount update of `cfile` if -ENOMEM is returned. To fix the bug, an extra goto label "out" is added, to make sure that the cleanup logic would always be respected. As the problem is caused by the allocation failure of `vars`, the cleanup logic between label "finished" and "out" can be safely ignored. According to the definition of function `is_replayable_error`, the error code of "-ENOMEM" is not recoverable. Therefore, the replay logic also gets ignored.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a7d5c294628088781da9e91cbb034d61c3a71f71 , < 3fc11ff13fbc2749871d6ac2141685cf54699997 (git)
Affected: a7d5c294628088781da9e91cbb034d61c3a71f71 , < 4191ea1f0bb3e27d65c5dcde7bd00e709ec67141 (git)
Affected: a7d5c294628088781da9e91cbb034d61c3a71f71 , < 4735f5991f51468b85affb8366b7067248457a71 (git)
Affected: a7d5c294628088781da9e91cbb034d61c3a71f71 , < cc82c6dff548f0066a51a6e577c7454e7d26a968 (git)
Affected: a7d5c294628088781da9e91cbb034d61c3a71f71 , < ab529e6ca1f67bcf31f3ea80c72bffde2e9e053e (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.8
Unaffected: 0 , < 5.8 (semver)
Unaffected: 6.1.150 , ≤ 6.1.* (semver)
Unaffected: 6.6.104 , ≤ 6.6.* (semver)
Unaffected: 6.12.45 , ≤ 6.12.* (semver)
Unaffected: 6.16.5 , ≤ 6.16.* (semver)
Unaffected: 6.17 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Siemens SIMATIC CN 4100 Affected: 0 , < V5.0 (custom)
guessed Create a notification for this product.
Show details on NVD website
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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.


Detection rules are retrieved from Rulezet.