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Vulnerability record · public intelligence
CVE-2020-25039
UNKNOWN

Insecure permissions on user namespace / fakeroot temporary rootfs in Singularity

Published Sep 16, 2020 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood2.01%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

Insecure permissions on user namespace / fakeroot temporary rootfs in Singularity

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

Insecure permissions on temporary directories used in fakeroot or user namespace container execution.

Potential impact

Insecure permissions on temporary directories used in fakeroot or user namespace container execution. When a Singularity action command (run, shell, exec) is run with the fakeroot or user namespace option, Singularity will extract a container image to a temporary sandbox directory. Due to insecure permissions on the temporary directory it is possible for any user with access to the system to read the contents of the image. Additionally, if the image contains a world-writable file or directory, it is possible for a user to inject arbitrary content into the running container.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. medium.com ↗
  2. Security advisory ↗
  3. openSUSE-SU-2020:1497 ↗
  4. openSUSE-SU-2020:1529 ↗

Record history

Published Sep 16, 2020 · Last refreshed Nov 3, 2026

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