CVE-2021-47356
Description
In the Linux kernel, the following vulnerability has been resolved: mISDN: fix possible use-after-free in HFC_cleanup() This module's remove path calls del_timer(). However, that function does not wait until the timer handler finishes. This means that the timer handler may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling del_timer_sync(), which makes sure the timer handler has finished, and unable to re-schedule itself.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No vendor mitigations ingested yet for this CVE. The mitigation-content worker queues fetches as references arrive — check back in a few minutes, or see the references list below.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rocky | 8 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 5.14.6-1 |
| debian | bullseye | fixed | 5.10.70-1 |
| debian | forky | fixed | 5.14.6-1 |
| debian | sid | fixed | 5.14.6-1 |
| debian | trixie | fixed | 5.14.6-1 |
| almalinux | 8 | fixed | kernel-rt-core-4.18.0-553.8.1.rt7.349.el8_10.x86_64.rpm |
References
- https://errata.rockylinux.org/RXSA-2024:4211
- https://errata.rockylinux.org/RLSA-2024:4352
- https://errata.rockylinux.org/RLSA-2024:4211
- https://www.suse.com/security/cve/CVE-2021-47356.html
- https://security-tracker.debian.org/tracker/CVE-2021-47356
- https://access.redhat.com/errata/RHSA-2024:4352
- https://bugzilla.redhat.com/1918601
- https://bugzilla.redhat.com/2248122
- https://bugzilla.redhat.com/2258875
- https://bugzilla.redhat.com/2265517
- https://bugzilla.redhat.com/2265519
- https://bugzilla.redhat.com/2265520
- https://bugzilla.redhat.com/2265800
- https://bugzilla.redhat.com/2266408
- https://bugzilla.redhat.com/2266831
- https://bugzilla.redhat.com/2267513
- https://bugzilla.redhat.com/2267518
- https://bugzilla.redhat.com/2267730
- https://bugzilla.redhat.com/2270093
- https://bugzilla.redhat.com/2271680
- https://bugzilla.redhat.com/2272692
- https://bugzilla.redhat.com/2272829
- https://bugzilla.redhat.com/2273204
- https://bugzilla.redhat.com/2273278
- https://bugzilla.redhat.com/2273423
💬 Discuss CVE-2021-47356 on VIR Community →
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.