Medium [CVE-2026-15812] access control list bypass via link ID spoofing on unencrypted dynamic links

A vulnerability was found in the internal Access Control List (ACL) subsystem of kronosnet (Version affected: <= 1.34).

When the framework is explicitly configured to manage dynamic links (accepting network traffic from any IP address) without network payload encryption, the validation architecture implicitly trusts the link ID provided within incoming data packets.

A remote, unauthenticated attacker can exploit this lack of validation by spoofing a legitimate link ID inside crafted network frames. This allows the attacker to fully bypass the ACL framework and inject arbitrary data packets into the application layer, potentially leading to data corruption or service instabilities.

Red Hat Product Security rates this vulnerability's impact as Low. Although the vulnerability allows an unauthenticated remote attacker to completely bypass the internal ACL layer and introduce arbitrary traffic, it depends entirely on a non-production configuration.

The exploit requires that kronosnet actively accept connections from any arbitrary IP (dynamic links) while simultaneously running completely unencrypted traffic.

Furthermore, this issue does not affect Red Hat Enterprise Linux High Availability (RHEL HA) or any official layered products, as Red Hat configurations securely enable network encryption by default, entirely mitigating the vulnerability's attack prerequisites.