"Verify All" Returns Success Despite Validation Failures in Singularity

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS

• CVE-2020-13846: 1.34% estimated exploitation activity in the next 30 days; percentile 71.25 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact The --all / -a option to singularity verify returns success even when some objects in a SIF container are not signed, or cannot be verified. The SIF objects that are not verified are reported in WARNING log messages, but a Container Verified message and exit code of 0 are returned. Workflows that verify a container using --all / -a and use the exit code as an indicator of success are vulnerable to running SIF containers that have unsigned, or modified, objects that may be exploited to introduce malicious behavior. Patches Singularity 3.6.0 has a new implementation of sign/verify that fixes this issue. All users are advised to upgrade to 3.6.0. Note that Singularity 3.6.0 uses a new signature format that is necessarily incompatible with Singularity < 3.6.0 - e.g. Singularity 3.5.3 cannot verify containers signed by 3.6.0. Version 3.6.0 includes a --legacy-insecure flag for the singularity verify command, that will perform verification of the older, and insecure, legacy…

Published by the source

20 Dec 2021, 18:24 UTC

Last modified by the source

20 Jan 2023, 22:03 UTC

Source last checked

26 Oct 2026, 14:54 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-6w7g-p4jh-rf92

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# Patch Next advisory brief: CVE-2020-13846

Advisory: "Verify All" Returns Success Despite Validation Failures in Singularity
IDs: CVE-2020-13846, GHSA-6w7g-p4jh-rf92
Record: https://patchnext.com/advisories/cve-2020-13846 (revision 1, source checked 26 Oct 2026, 14:54 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/sylabs/singularity 3.6.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/sylabs/singularity: affected >= 3.5.0, < 3.6.0; fixed in 3.6.0

## Suggested inspection (read-only)
- Go github.com/sylabs/singularity: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/sylabs/singularity.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-6w7g-p4jh-rf92 (GitHub-reviewed advisory GHSA-6w7g-p4jh-rf92 lists affected ranges: Go github.com/sylabs/singularity >=3.5.0 <3.6.0)

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