CVE-2021-32635

Action Commands (run/shell/exec) Against Library URIs Ignore Configured Remote Endpoint

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.

Category

6.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.63%
Vendor Advisory gentoo.org
Affected: sylabs singularity
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-32635?
CVE-2021-32635 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32635?
To fix CVE-2021-32635, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32635 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-32635 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32635?
CVE-2021-32635 affects sylabs singularity.
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