CVE-2026-56098 (CVSS 4.3)

Description

A flaw was found in rubygem-katello. The RegistryProxiesController in Katello contains an authorization bypass vulnerability due to an execution fall-through in the registry_authorize filter. While the application identifies unauthorized requests and triggers an error response via the unauthorized method, it fails to halt the execution of the current code path (missing return statement). This failure in the control flow allows the application to proceed into subsequent business logic and database validation filters. Consequently, the application reveals its internal state through differential responses, allowing an unprivileged attacker to enumerate valid Users, Organizations, and Products across the entire instance.

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CVSS v3.1 Score

4.3

MEDIUM

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

EPSS — Exploit Prediction

0.0031

Probability of exploitation

0.21%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-203 CWE-203

References

Other References

https://access.redhat.com/errata/RHSA-2026:74503 https://access.redhat.com/errata/RHSA-2026:74504 https://access.redhat.com/errata/RHSA-2026:74505 https://access.redhat.com/errata/RHSA-2026:74506 https://access.redhat.com/security/cve/CVE-2026-56098 https://bugzilla.redhat.com/show_bug.cgi?id=2490542 http://www.openwall.com/lists/oss-security/2026/10/07/3

Frequently Asked Questions

What is CVE-2026-56098? +

A flaw was found in rubygem-katello. The RegistryProxiesController in Katello contains an authorization bypass vulnerability due to an execution fall-through in the registry_authorize filter. While the application identifies unauthorized requests and triggers an error response via the unauthorized method, it fails to halt the execution of the current code path (missing return statement). This failure in the control flow allows the application to proceed into subsequent business logic and database validation filters. Consequently, the application reveals its internal state through differential responses, allowing an unprivileged attacker to enumerate valid Users, Organizations, and Products across the entire instance. It has a CVSS v3.1 base score of 4.3 (MEDIUM).

How severe is CVE-2026-56098? +

CVE-2026-56098 has a CVSS v3.1 score of 4.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0031, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-56098? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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