CVE-2025-40103 json
smb: client: Fix refcount leak for cifs_sb_tlink
published 2025-10-30 12 mo ago modified 2026-10-19 20 d ago also EUVD-2025-36975
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 10%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
smb: client: Fix refcount leak for cifs_sb_tlink
Fix three refcount inconsistency issues related to `cifs_sb_tlink`.
Comments for `cifs_sb_tlink` state that `cifs_put_tlink()` needs to be called after successful calls to `cifs_sb_tlink()`. Three calls fail to update refcount accordingly, leading to possible resource leaks.
Patch / fix
- Linux Linux 5.15.203, 6.1.158, 6.6.114, 6.12.55, 6.17.5, 6.18
- linux Debian 12 6.1.158-1
- linux Debian 13 6.12.57-1
- linux Debian 14 6.17.6-1
debian advisories DEBIAN-CVE-2025-40103
- linux Ubuntu 22.04 LTS 5.15.0-186.196
- linux Ubuntu 24.04 LTS 6.8.0-106.106
- linux Ubuntu 25.10 6.17.0-14.14
- linux-aws Ubuntu 22.04 LTS 5.15.0-1112.119
- linux-aws Ubuntu 24.04 LTS 6.8.0-1050.53
- linux-aws Ubuntu 25.10 6.17.0-1007.7
- linux-gcp Ubuntu 22.04 LTS 5.15.0-1112.122
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1052.55
ubuntu advisories UBUNTU-CVE-2025-40103
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.34.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.34.1
- kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
- kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.34.1
- kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1
- kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.34.1
- kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.34.1.150700.17.23.1
suse advisories SUSE-SU-2026:1081-1SUSE-SU-2026:1078-1SUSE-SU-2026:1041-1SUSE-SU-2026:20873-1SUSE-SU-2026:20838-1SUSE-SU-2026:20931-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.27.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.27.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.27.1
opensuse advisories openSUSE-SU-2026:20416-1openSUSE-SU-2026:10301-1openSUSE-SU-2025:15702-1
- git.kernel.org/stable/c/d3c8ea197055c260119a13360e8202a27e53e1e4 commit
- git.kernel.org/stable/c/790282abe9d805f08618c1c24ea2529e7259b692 commit
- git.kernel.org/stable/c/d7dd034c14928306db1b46be277ae439b84dacf9 commit
- git.kernel.org/stable/c/e15605b68b490186da2ad8029c0351a9cfb0b9af commit
- git.kernel.org/stable/c/896bb31e1416f582503db1350cf1bd10dc64e5a6 commit
- git.kernel.org/stable/c/c2b77f42205ef485a647f62082c442c1cd69d3fc commit
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 10% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/d3c8ea197055c260119a13360e8202a27e53e1e4
- git.kernel.org /stable/c/790282abe9d805f08618c1c24ea2529e7259b692
- git.kernel.org /stable/c/d7dd034c14928306db1b46be277ae439b84dacf9
- git.kernel.org /stable/c/e15605b68b490186da2ad8029c0351a9cfb0b9af
- git.kernel.org /stable/c/896bb31e1416f582503db1350cf1bd10dc64e5a6
- git.kernel.org /stable/c/c2b77f42205ef485a647f62082c442c1cd69d3fc
Sources
- CVE List CVE-2025-40103
- NVD CVE-2025-40103
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