# CVE-2026-75939: Red Hat oc-mirror PGP signature verification bypass

Source: https://junglewise.ai/threats/cve-2026-75939-a-flaw-was-found-in-openshift-oc-mirror-the-tool-incorrectly  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-21. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-75939 · Severity: high · CVSS 7.4 · Published 2026-09-21

Red Hat's oc-mirror tool, used to manage container image registries in disconnected OpenShift environments, contains a flaw in how it verifies the authenticity of release images using PGP signatures. An attacker who can intercept network traffic can forge a malicious release payload that the tool will accept as legitimate, allowing compromised container images to be mirrored into production registries and potentially compromising all deployments that use those images.

Technologies: [Red Hat Oc-Mirror](https://junglewise.ai/threats/technologies/oc-mirror). Vendors: [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-75939 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-75939 being exploited in the wild.

**How severe is CVE-2026-75939?** High severity, with a CVSS score of 7.4, published 21 September 2026.

**Which products and versions are affected?** Red Hat oc-mirror.

**Is there a fix for CVE-2026-75939?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-75939 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-75939?** Check whether you run Red Hat Oc-Mirror. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability stems from improper verification of PGP cryptographic signatures (CWE-347): the tool checks for signature errors before the entire signed message body is processed, allowing an attacker to craft a PGP message with a valid Red Hat release key ID but a forged signature that bypasses validation. An unauthenticated remote attacker with the ability to intercept or manipulate traffic to the signature endpoint can exploit this to inject malicious container images. A mitigation or patch is not currently available.

## Affected products

- Red Hat oc-mirror

## Timeline

- 2026-09-21: disclosed

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-75939](https://access.redhat.com/security/cve/CVE-2026-75939)

## Related threats

- [oc-mirror unauthenticated registry access on all interfaces](https://junglewise.ai/threats/cve-2026-96577-a-flaw-was-found-in-oc-mirror-during-mirroring-operations-the)
- [OpenShift oc-mirror path traversal in operator catalog extraction](https://junglewise.ai/threats/cve-2026-101295-path-traversal-arbitrary-file-write-in-oc-mirror-s-operator)