OSV-2021-421 Heap-use-after-free in __cil_verify_classperms
A heap-use-after-free vulnerability in the SELinux policy compiler allows attackers to cause denial of service or potentially execute code via crafted policy files.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Not stated
- Victim action needed
- Not needed
- Fix
- None listed
What is OSV-2021-421?
OSV-2021-421 is an use after free vulnerability in selinux, published on 20 Feb 2021.
Official description
OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31124
Crash type: Heap-use-after-free READ 8
Crash state:
__cil_verify_classperms
__verify_map_perm_classperms
hashtab_map
Which versions are affected by OSV-2021-421?
1 open source package ship an affected version, including selinux.
| Package | Affected | Fixed in |
|---|---|---|
selinux OSS-Fuzz | All versions | None |
How do I fix OSV-2021-421?
No fix has been published for OSV-2021-421 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is OSV-2021-421 being exploited?
There is no known exploitation of OSV-2021-421 in the wild and no public exploit code.