Red Hat Kroxylicious ACL Authorizer improper authorization

Summaryinfo

A vulnerability, which was classified as critical, has been found in Red Hat Kroxylicious. Affected is an unknown function of the component ACL Authorizer. This manipulation causes improper authorization. This vulnerability appears as CVE-2026-128424. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability was found in Red Hat Kroxylicious (affected version unknown). It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component ACL Authorizer. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in Kroxylicious. The ACL authorizer's rules-file parser unquotes `matching /…/` regular-expression literals using the string unquoting rules, which strips every backslash escape. As a result, an allow rule such as `matching /orders\.v1/` is compiled as the regex `orders.v1`, which also matches unintended names such as `ordersXv1`, and character classes such as `\d` and `\w` lose their special meaning. Allow rules written with regex escapes can therefore apply to more resources than the author intended. Depending on the ACL configuration, this may allow an authenticated Kafka client to access a resource (such as read or write a topic) that should have been denied.

The advisory is shared at access.redhat.com. This vulnerability is known as CVE-2026-128424 since 11/13/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Red Hat

Name

• Kroxylicious

License

• open-source

Website

• Vendor: https://www.redhat.com/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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