CVE-2018-12015

In Perl through 5.26.2, the Archive::Tar module allows remote attackers to bypass a directory-traversal protection mechanism, and overwrite arbitrary files, via an archive file containing a symlink and a regular file with the same name.

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://seclists.org/fulldisclosure/2019/Mar/49
• http://www.securityfocus.com/bid/104423
• http://www.securitytracker.com/id/1041048
• https://access.redhat.com/errata/RHSA-2019:2097
• https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=900834
• https://seclists.org/bugtraq/2019/Mar/42
• https://security.netapp.com/advisory/ntap-20180927-0001/
• https://support.apple.com/kb/HT209600
• https://usn.ubuntu.com/3684-1/
• https://usn.ubuntu.com/3684-2/
• https://www.debian.org/security/2018/dsa-4226
• https://www.oracle.com/security-alerts/cpujul2020.html