CVE-2025-40103 | smb: client: Fix refcount leak for cifs_sb_tlink

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.

Published: 2025-10-30 Last update: 2026-04-18 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2025-40103 is rated Low Risk (6.4/100): low exploitation likelihood (EPSS 0.17%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-40103

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 0.17% +0.11%
2 2026-04-09 0.04% 0.06% +0.01%
3 2026-03-28 0.04%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-40103

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2025-40103

GitHub Security Advisory for CVE-2025-40103

GHSA-rg54-mxfq-r39j · Severity: unknown — In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix refcount...

OS Trackers for CVE-2025-40103

vendor priority summary link
debian not yet assigned CVE-2025-40103 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5, open 1. https://security-tracker.debian.org/tracker/CVE-2025-40103
redhat low https://access.redhat.com/security/cve/CVE-2025-40103
suse low CVE-2025-40103 severity low: SUSE including 488 source package names (2.1.3-6.124:kernel-default-base-6.4.0-40.1.21.17, 2.1.3-7.105:kernel-default-6.4.0-40.1, …), 731 product×package rows across 47 product lines (Container suse/sl-micro/6.0/base-os-container, Container suse/sl-micro/6.0/kvm-os-container, … (47 product lines)): Fixed 462, Known Affected 231, First Fixed 32, Known Not Affected 6. https://www.suse.com/security/cve/CVE-2025-40103/
ubuntu medium CVE-2025-40103 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 181, released 127, needed 81, not-affected 4, pending 2. https://ubuntu.com/security/CVE-2025-40103

Affected software / configurations for CVE-2025-40103

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-40103

cvelogic Threat Intelligence