CVE-2021-32635 Information

Description

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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

Reference

https://github.com/sylabs/singularity/security/advisories/GHSA-5mv9-q7fq-9394 https://github.com/sylabs/singularity/releases/tag/v3.7.4 https://security.gentoo.org/glsa/202107-50

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

REQUIRED

Confidentiality Impact

UNCHANGED

Integrity Impact

LOW

Availability Impact

LOW

Base Score

LOW

Base Severity

6.3