Malicious release mirroring via premature signature check
Published Sep 21, 2026 · Updated Sep 21, 2026
Signature verification bypass in Red Hat OpenShift Container Platform 4 allows remote attackers to mirror malicious release payloads. The oc-mirror tool checks for OpenPGP signature errors before consuming the complete signed body, so a forged signature bearing a valid Red Hat key ID is accepted. Exploitation requires interception or manipulation of traffic to the signature endpoint and can introduce attacker-controlled release content into a disconnected registry.
Summary
What happened
Signature verification bypass in Red Hat OpenShift Container Platform 4 allows remote attackers to mirror malicious release payloads. The oc-mirror tool checks for OpenPGP signature errors before consuming the complete signed body, so a forged signature bearing a valid Red Hat key ID is accepted. Exploitation requires interception or manipulation of traffic to the signature endpoint and can introduce attacker-controlled release content into a disconnected registry.
The record
- CVE
- CVE-2026-75939
- Published
- Sep 21, 2026
- Updated
- Sep 21, 2026
- Vendor
- Commonhaus Foundation
- Product
- Red Hat OpenShift Container Platform 4
- Classifications
- CWE-347, T1195.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 21, 2026CVE publishedPublication date reported by the CVE source.
- Sep 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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