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Vulnerability record · CVE-2026-75939 · published 21 September 2026

CVE-2026-75939: Improper verification of cryptographic signature vulnerability

A flaw was found in openshift/oc-mirror. The tool incorrectly verifies PGP (Pretty Good Privacy) release image signatures by checking for signature errors before the entire signed body is processed, leading to a bypass of the signature verification. A remote attacker, by intercepting or manipulating network traffic to the signature endpoint, could exploit this to craft a PGP message with a valid Red Hat release key ID but a forged signature. This enables the `oc-mirror` tool to accept and mirror a malicious release payload into a disconnected registry, potentially compromising the integrity of software deployments.

7.4 CVSS 3.1 High EPSS 0.31% · top 78.5% CWE-347 · Improper verification of cryptographic signature Awaiting Analysis
7.4CVSS 3.1 base score
0.31%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
2References
24 Sep 2026Last modified by NVD

Description

A flaw was found in openshift/oc-mirror. The tool incorrectly verifies PGP (Pretty Good Privacy) release image signatures by checking for signature errors before the entire signed body is processed, leading to a bypass of the signature verification. A remote attacker, by intercepting or manipulating network traffic to the signature endpoint, could exploit this to craft a PGP message with a valid Red Hat release key ID but a forged signature. This enables the `oc-mirror` tool to accept and mirror a malicious release payload into a disconnected registry, potentially compromising the integrity of software deployments.

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

References

LinkTags
https://access.redhat.com/security/cve/CVE-2026-75939
https://bugzilla.redhat.com/show_bug.cgi?id=2517976

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Source: NIST National Vulnerability Database (record CVE-2026-75939), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.