CVE-2021-32635

Summary

Singularity is an open source container platform. In verions 3.7.2 and 3.7.3, Dde to incorrect use of a default URL, singularity action commands (run/shell/exec) specifying a container using a library:// URI will always attempt to retrieve the container from the default remote endpoint (cloud.sylabs.io) rather than the configured remote endpoint. An attacker may be able to push a malicious container to the default remote endpoint with a URI that is identical to the URI used by a victim with a non-default remote endpoint, thus executing the malicious container. Only action commands (run/shell/exec) against library:// URIs are affected. Other commands such as pull / push respect the configured remote endpoint. The vulnerability is patched in Singularity version 3.7.4. Two possible workarounds exist: Users can only interact with the default remote endpoint, or an installation can have an execution control list configured to restrict execution to containers signed with specific secure keys.

Affected Software

VendorProductVersion RangeStatus
sylabssingularity>= 3.7.2, <= 3.7.3affected

Weaknesses

  • CWE-923: CWE-923: Improper Restriction of Communication Channel to Intended Endpoints
  • CWE-20: CWE-20 Improper Input Validation

ADP Enrichment

CVE Program Container

Additional References

References