CVE-2021-20321
A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.
02 / AFFECTED SOFTWARE
Affected packages
1 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In ovl_rename of dir.c, there is a possible out of bounds write due to a race condition. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.
05 / REFERENCES
Further evidence
- https://android.googlesource.com/kernel/common/+/9763ffd4da217
- https://source.android.com/security/bulletin/2022-06-01
- https://bugzilla.redhat.com/show_bug.cgi?id=2013242
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html
- https://lore.kernel.org/all/20211011134508.748956131%40linuxfoundation.org/
- https://www.debian.org/security/2022/dsa-5096