What is CVE-2021-29499?

CVE-2021-29499 is a high-severity vulnerability in Sylabs Sif, classified under Use of Insufficiently Random Values. CVSS score: 7.5/10. Published 2021-05-07.

How severe is CVE-2021-29499?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Sylabs Sif

CVE-2021-29499

SIF is an open source implementation of the Singularity Container Image Format. The `siftool new` command and func siftool.New() produce predictable UUID identifiers due to insecure randomness in the version of the `github.com/satori/go.uuid` module used as a dependency. A patch is available in version >= v1.2.3 of the module. Users are encouraged to upgrade. As a workaround, users passing CreateInfo struct should ensure the `ID` field is generated using a version of `github.com/satori/go.uuid` that is not vulnerable to this issue.

Published 2021-05-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.010 (60.0th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 60.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Sylabs Sif — versions <= 1.2.2
Sylabs Singularity Image Format

Weakness classification (CWE)

CWE-330 — Use of Insufficiently Random Values

References

github.com/sylabs/sif/security/advisories/GHSA-4gh8-x3vv-phhg (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-29499?: CVE-2021-29499 is a high-severity vulnerability in Sylabs Sif, classified under Use of Insufficiently Random Values. CVSS score: 7.5/10. Published 2021-05-07.
How severe is CVE-2021-29499?: High severity. CVSS v3 base score is 7.5 out of 10.