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).

Affected: Ubuntu:Pro:16.04:LTS: libsepol, Ubuntu:18.04:LTS: libsepol, Ubuntu:20.04:LTS: libsepol

Nicolas Iooss discovered that libsepol incorrectly handled memory when handling policies. An attacker could possibly use this issue to cause a crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-36084)

It was discovered that libsepol incorrectly handled memory when handling policies. An attacker could possibly use this issue to cause a crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-36085)

It was discovered that libsepol incorrectly handled memory when handling policies. An attacker could possibly use this issue to cause a crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affects Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 21.10. (CVE-2021-36086)

It was discovered that libsepol incorrectly validated certain data, leading to a heap overflow. An attacker could possibly use this issue to cause a crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-36087)