What is CVE-2025-39720?

CVE-2025-39720 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2025-09-05.

How severe is CVE-2025-39720?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2025-39720 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Linux

CVE-2025-39720

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.

EPSS: 0.003 (20.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Linux — versions 0626e6641f6b467447c81dd7678a69c66f7746cf, 5.15, 0
Linux Linux_kernel — versions 6.17

Public proof-of-concept exploits

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)

Frequently asked questions

What is CVE-2025-39720?: CVE-2025-39720 is a high-severity vulnerability in Linux. CVSS score: 7.5/10. Published 2025-09-05.
How severe is CVE-2025-39720?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-39720 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.