CVE-2022-31250: 
Linux openSUSE vulnerability analysis and mitigation

A UNIX Symbolic Link (Symlink) Following vulnerability (CVE-2022-31250) was discovered in keylime of openSUSE Tumbleweed. The vulnerability was disclosed on July 20, 2022, and affects the keylime package, specifically the post-installation script functionality (NVD).

The vulnerability exists in the post-installation script of keylime-tpmcertstore package, where unsafe chown operations are performed on files and directories that could be influenced by unprivileged users. The issue is classified as CWE-59 (Symlink Following) and received a CVSS score of 7.8 (SUSE Bugzilla).

This vulnerability allows local attackers with keylime user privileges to escalate their permissions to root through symbolic link manipulation. The attacker could exploit this to take ownership of arbitrary files in the system, including critical system files like /etc/passwd (SUSE Bugzilla).

The issue was addressed by removing the unsafe chown calls from the post-installation script. For necessary ownership changes, secure alternatives using chown -h were implemented to modify only the symbolic links themselves rather than following them. The fix was released as part of SUSE-SU-2022:2658-1 update (SUSE Bugzilla).