CVE-2021-21272

CVE-2021-21272 is a high-severity vulnerability in Deislabs Oras with a CVSS 3.x base score of 7.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-59.

Key facts

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.

Frequently asked questions

What is CVE-2021-21272?
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.
How severe is CVE-2021-21272?
CVE-2021-21272 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-21272 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21272?
CVE-2021-21272 affects Deislabs Oras. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21272?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-21272 published?
CVE-2021-21272 was published on 2021-01-25 and last updated on 2026-06-17.

References

Affected products (1)

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