CVE-2026-75939
HIGH 7.4A 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.
Severe if exploited (CVSS 7.4), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.4%chance of exploitation in 30 days · 30th percentile
Impact if exploited
7.4CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ⚠Complexity: Needs a race window or specific setup
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-75939/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-75939/poc.json
Affected
Vendors Red Hat
Products Red Hat Openshift Container Platform 4.18 Red Hat Openshift Container Platform 4
Weakness (CWE)
- CWE-347: Improper Verification of Cryptographic Signature
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
All CVSS metrics
- HIGH 7.4 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - HIGH 7.4 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N