CVE-2019-18898

UNIX Symbolic Link (Symlink) Following vulnerability in the trousers package of SUSE Linux Enterprise Server 15 SP1; openSUSE Factory allowed local attackers escalate privileges from user tss to root. This issue affects: SUSE Linux Enterprise Server 15 SP1 trousers versions prior to 0.3.14-6.3.1. openSUSE Factory trousers versions prior to 0.3.14-7.1.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

Potential Mitigations

• Follow the principle of least privilege when assigning access rights to entities in a software system.
• Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/132.html
• https://cwe.mitre.org/data/definitions/17.html
• https://cwe.mitre.org/data/definitions/35.html
• https://cwe.mitre.org/data/definitions/76.html

References

• http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00066.html
• https://bugzilla.suse.com/show_bug.cgi?id=1157651