{"id":"CVE-2021-32635","details":"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.","aliases":["GHSA-5mv9-q7fq-9394"],"modified":"2026-04-16T04:31:50.386584380Z","published":"2021-05-28T21:15:09.020Z","related":["GHSA-5mv9-q7fq-9394","openSUSE-SU-2024:11384-1"],"references":[{"type":"ADVISORY","url":"https://github.com/sylabs/singularity/releases/tag/v3.7.4"},{"type":"ADVISORY","url":"https://github.com/sylabs/singularity/security/advisories/GHSA-5mv9-q7fq-9394"},{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/202107-50"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/sylabs/singularity","events":[{"introduced":"0"},{"last_affected":"47d3b5d415166bb3e0abba36c70714b53f240f70"},{"introduced":"0"},{"last_affected":"6e59f31cb97ff59e323850aa1339a38a11358429"},{"fixed":"a29667c1564e5a689719ca762feedf050ed4933f"}],"database_specific":{"versions":[{"introduced":"0"},{"last_affected":"3.7.2"},{"introduced":"0"},{"last_affected":"3.7.3"}]}}],"versions":["1.0","2.0","2.1","2.1.1","2.1.2","2.2","2.3","2.3.1","2.3.2","2.4","v3.0.0","v3.0.0-alpha.1","v3.0.0-beta.1","v3.0.1","v3.1.0","v3.1.0-rc1","v3.1.0-rc2","v3.1.0-rc3","v3.1.0-rc4","v3.2.0-rc1","v3.3.0-rc.1","v3.4.0-rc.1","v3.7.0","v3.7.0-rc.1","v3.7.0-rc.2","v3.7.1","v3.7.2","v3.7.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-32635.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L"}]}