CVE-2021-32635

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.

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.

### Impact Due 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. ### Patches All users should upgrade to Singularity 3.7.4 or later. A patch was applied at: https://github.com/sylabs/singularity/commit/d52ae9d13979733c5e987a566fae59ed6f1bf796 ### Workarounds Users who only interact with the default remote endpoint are not affected. Installations with an execution control list configured to restrict execution to containers signed with specific secure keys are not affected. ### For more information General questions about the impact of the advisory can be asked in the: - [SingularityCE Slack Channel](https://singularityce.slack.com) - [SingularityCE Mailing List](https://groups.google.com/g/singularity-ce) Any sensitive security concerns should be directed to: security@sylabs.io See our Security Policy here: https://sylabs.io/security-policy

### Impact Due 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. ### Patches All users should upgrade to Singularity 3.7.4 or later. A patch was applied at: https://github.com/sylabs/singularity/commit/d52ae9d13979733c5e987a566fae59ed6f1bf796 ### Workarounds Users who only interact with the default remote endpoint are not affected. Installations with an execution control list configured to restrict execution to containers signed with specific secure keys are not affected. ### For more information General questions about the impact of the advisory can be asked in the: - [SingularityCE Slack Channel](https://singularityce.slack.com) - [SingularityCE Mailing List](https://groups.google.com/g/singularity-ce) Any sensitive security concerns should be directed to: security@sylabs.io See our Security Policy here: https://sylabs.io/security-policy

Singularity es una plataforma de contenedores de código abierto. En las versiones 3.7.2 y 3.7.3, debido al uso incorrecto de una URL por defecto, los comandos de acción de `singularity` (`run`/`shell`/`exec`) que especifican un contenedor utilizando una URI `library://` siempre intentarán recuperar el contenedor desde el punto final remoto por defecto (`cloud.sylabs.io`) en lugar del punto final remoto configurado. Un atacante puede ser capaz de empujar un contenedor malicioso al punto final remoto por defecto con un URI que es idéntico al URI utilizado por una víctima con un punto final remoto no predeterminado, ejecutando así el contenedor malicioso. Sólo se ven afectados los comandos de acción (`run`/`shell`/`exec`) contra URIs `library://`. Otros comandos como `pull` / `push` respetan el endpoint remoto configurado. La vulnerabilidad está parcheada en la versión 3.7.4 de Singularity. Existen dos posibles soluciones: Los usuarios sólo pueden interactuar con el endpoint remoto por defecto, o una instalación puede tener una lista de control de ejecución configurada para restringir la ejecución a contenedores firmados con claves seguras específicas