CVE-2025-39819
Description
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| rocky | 9 | fixed | |
| debian | bookworm | fixed | 6.1.153-1 |
| debian | bullseye | fixed | 6.1.153-1~deb11u1 |
| debian | forky | fixed | 6.16.5-1 |
| debian | sid | fixed | 6.16.5-1 |
| debian | trixie | fixed | 6.12.48-1 |
| linux-kernel | affected | 6.1.150 | |
| linux-kernel | 6.17 | affected | |
| debian | 11.0 | affected | |
References
- https://access.redhat.com/errata/RHSA-2025:19105
- https://git.kernel.org/stable/c/3fc11ff13fbc2749871d6ac2141685cf54699997
- https://git.kernel.org/stable/c/4191ea1f0bb3e27d65c5dcde7bd00e709ec67141
- https://git.kernel.org/stable/c/4735f5991f51468b85affb8366b7067248457a71
- https://git.kernel.org/stable/c/ab529e6ca1f67bcf31f3ea80c72bffde2e9e053e
- https://git.kernel.org/stable/c/cc82c6dff548f0066a51a6e577c7454e7d26a968
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- https://www.suse.com/security/cve/CVE-2025-39819.html
- https://errata.rockylinux.org/RLSA-2025:19105
- https://security-tracker.debian.org/tracker/CVE-2025-39819
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.