CVE-2025-39825

low-risk
Published 2025-09-16

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix race with concurrent opens in rename(2) Besides sending the rename request to the server, the rename process also involves closing any deferred close, waiting for outstanding I/O to complete as well as marking all existing open handles as deleted to prevent them from deferring closes, which increases the race window for potential concurrent opens on the target file. Fix this by unhashing the dentry in advance to prevent any concurrent opens on the target.

Do I need to act?

-
0.01% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
4
CVSS 4.7/10 Medium
LOCAL / HIGH complexity

Affected Products (3)

Affected Vendors

Debian Linux

References (6)

Patch https://git.kernel.org/stable/c/24b9ed739c8c5b464d983e12cf308982f3ae93c2
Patch https://git.kernel.org/stable/c/289f945acb20b9b54fe4d13895e44aa58965ddb2
Patch https://git.kernel.org/stable/c/c9991af5e09924f6f3b3e6996a5e09f9504b4358
Patch https://git.kernel.org/stable/c/c9e7de284da0be5b44dbe79d71573f9f7f9b144c
Patch https://git.kernel.org/stable/c/d84291fc7453df7881a970716f8256273aca5747
Mailing List https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
21
/ 100
low-risk
Severity 12/34 · Low
Exploitability 0/34 · Minimal
Exposure 9/34 · Low