CVE-2020-26312

Technical Description

Dotmesh is a git-like command-line interface for capturing, organizing and sharing application states. In versions 0.8.1 and prior, the unsafe handling of symbolic links in an unpacking routine may

enable attackers to read and/or write to arbitrary locations outside the

designated target folder. The routine `untarFile` attempts to guard against creating symbolic links that point outside the directory a tar archive is extracted to. However, a malicious tarball first linking `subdir/parent` to `..` (allowed, because `subdir/..` falls within the archive root) and then linking `subdir/parent/escapes` to `..` results in a symbolic link pointing to the tarball’s parent directory, contrary to the routine’s goals. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, they may be able to read arbitrary system files the par

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References