CVE-2026-12852

A flaw was found in Bouncy Castle for Java. A remote attacker could exploit this by providing a specially crafted message to the MLS wire decoder. The decoder allocates an attacker-declared opaque length without first performing a bounds check. This can lead to excessive memory allocation, resulting in a Denial of Service (DoS) for the application.

This vulnerability targets the Messaging Layer Security (MLS) module, which in Bouncy Castle is packaged as bcmls. No Red Hat products are affected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.