The CIL compiler in SELinux 3.2 has a use-after-free in __cil_verify_classperms (called from __cil_verify_classpermission and __cil_pre_verify_helper).
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
Link | Tags |
---|---|
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/selinux/OSV-2021-417.yaml | third party advisory |
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31065 | issue tracking patch exploit third party advisory |
https://github.com/SELinuxProject/selinux/commit/f34d3d30c8325e4847a6b696fe7a3936a8a361f3 | third party advisory patch |
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/U7ZYR3PIJ75N6U2IONJWCKZ5L2NKJTGR/ | vendor advisory |