CVE-2021-44733
Medium
Elevated severity or exploit probability.
CVSS base
7.0
HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
0.7%
51.7th percentile
CISA KEV
Not listed
Weakness / dates
CWE-362
Published 2021-12-22 · modified 2026-08-05
CVSS breakdown
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | L | Local |
| Attack Complexity | H | High |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2021-12-22 — Published (NVD)
- 2026-08-05 — Last modified (NVD)
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.
Affected
References
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=dfd0743f1d9ea76931510ed150334d571fbab49d
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/drivers/tee/tee_shm.c
- exploit https://github.com/pjlantz/optee-qemu/blob/main/README.md
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
- https://lore.kernel.org/lkml/20211215092501.1861229-1-jens.wiklander%40linaro.org/
- https://security.netapp.com/advisory/ntap-20220114-0003/
- https://www.debian.org/security/2022/dsa-5096
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=dfd0743f1d9ea76931510ed150334d571fbab49d
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/drivers/tee/tee_shm.c
- exploit https://github.com/pjlantz/optee-qemu/blob/main/README.md
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
- https://lore.kernel.org/lkml/20211215092501.1861229-1-jens.wiklander%40linaro.org/
- https://security.netapp.com/advisory/ntap-20220114-0003/
- https://www.debian.org/security/2022/dsa-5096