CVE-2025-40285
Unknown Unknown - Not Provided
BaseFortify

Publication date: 2025-12-06

Last updated on: 2025-12-08

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: smb/server: fix possible refcount leak in smb2_sess_setup() Reference count of ksmbd_session will leak when session need reconnect. Fix this by adding the missing ksmbd_user_session_put().
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2025-12-06
Last Modified
2025-12-08
Generated
2026-06-16
AI Q&A
2025-12-07
EPSS Evaluated
2026-06-14
NVD
CVE-2025-40285
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel *
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Executive Summary

This vulnerability is a reference count leak in the Linux kernel's SMB server component (smb/server). Specifically, the reference count of ksmbd_session can leak when a session needs to reconnect because the function smb2_sess_setup() was missing a call to ksmbd_user_session_put(), which is necessary to properly decrement the reference count and avoid resource leaks.

Impact Analysis

The reference count leak can lead to resource exhaustion over time, potentially causing degraded system performance or instability in the SMB server functionality on the Linux kernel. This could affect file sharing services relying on SMB, possibly leading to denial of service or other operational issues.

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2025-40285. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart