CVE-2021-21272: zip slip in ORAS

Vulnerability summary

CVE-2021-21272 is a high (CVSS 7.7) vulnerability in deislabs oras. EPSS estimates a 1.47% chance of exploitation in the next 30 days, higher than 73.7% of scored vulnerabilities.

Timeline

1. 25-01-2021
   PublishedVulnerability first disclosed.
2. 03-08-2024
   Last modifiedVulnerability information updated.

Description

ORAS is open source software which enables a way to push OCI Artifacts to OCI Conformant registries. ORAS is both a CLI for initial testing and a Go Module. In ORAS from version 0.4.0 and before version 0.9.0, there is a "zip-slip" vulnerability. The directory support feature allows the downloaded gzipped tarballs to be automatically extracted to the user-specified directory where the tarball can have symbolic links and hard links. A well-crafted tarball or tarballs allow malicious artifact providers linking, writing, or overwriting specific files on the host filesystem outside of the user-specified directory unexpectedly with the same permissions as the user who runs `oras pull`. Users of the affected versions are impacted if they are `oras` CLI users who runs `oras pull`, or if they are Go programs, which invoke `github.com/deislabs/oras/pkg/content.FileStore`. The problem has been fixed in version 0.9.0. For `oras` CLI users, there is no workarounds other than pulling from a trusted artifact provider. For `oras` package users, the workaround is to not use `github.com/deislabs/oras/pkg/content.FileStore`, and use other content stores instead, or pull from a trusted artifact provider.

• CWE-22Improper Limitation of a Pathname to a Restricted DirectoryThe product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
• CWE-59Improper Link Resolution Before File AccessThe 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.