What’s Vulnerable › Vulnerabilities

CVE-2025-39720: ksmbd: fix refcount leak causing resource not released

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-09-05 · updated 2026-10-30

Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix refcount leak causing resource not released When ksmbd_conn_releasing(opinfo->conn) returns true,the refcount was not decremented properly, causing a refcount leak that prevents the count from reaching zero and the memory from being released.

Affected products

• Linux kernel: from 5.15 before 6.6.103; from 6.7 before 6.12.44; from 6.13 before 6.16.4; 6.17-rc1, 6.17-rc2 — fixed in 6.6.103, 6.12.44, 6.16.4
• Linux: 5.15 — fixed in 6.17

How to fix

Upgrade to a fixed version: Linux kernel 6.6.103, 6.12.44, 6.16.4; Linux 6.17. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/263680d314eaaa27334f486d86c9fe7d19f50c8a
• https://git.kernel.org/stable/c/36e010bb865fbaa1202fe9bcce3fd486d6db7606
• https://git.kernel.org/stable/c/89bb430f621124af39bb31763c4a8b504c9651e2
• https://git.kernel.org/stable/c/9a7abce6e8c0e2145b346a6d4abf0d9655e9b0e8
• https://git.kernel.org/stable/c/a1d2bab4d53368a526c97aba92671dd71814f95a

Get alerted when CVE-2025-39720 or the next vulnerability affects your stack