CVE-2021-32635
Fixed in a distro release EPSS 1%CVSS 6.3
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.
Products: sylabs singularity
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Go | github.com/sylabs/singularity | 3.7.4 |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu 25.10 | singularity-container | no fix |
| Ubuntu 26.04 LTS | singularity-container | no fix |
| Ubuntu Pro 18.04 LTS | singularity-container | no fix |
| Ubuntu Pro 24.04 LTS | singularity-container | no fix |
| openSUSE Tumbleweed | singularity | 3.8.3-1.2 |