Memory Exhaustion Vulnerability in Rancher Manager Server by Rancher

CVE-2026-59675

What is CVE-2026-59675?

A vulnerability exists in Rancher Manager's API audit logging that allows an unauthenticated attacker to exploit unbounded HTTP request body sizes. When this feature is enabled, the middleware can read entire HTTP request bodies without enforcing a size limit on login endpoints. This occurs because the audit logging middleware operates before the APIBodyLimitingHandler, effectively bypassing the default body-size cap of 1 MiB. As a result, attackers can send excessively large request bodies to the public login endpoints, leading to memory exhaustion issues in the Rancher Manager server. This overload can result in the termination of the Rancher API and UI, disrupting management functionalities for all associated clusters.

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