CVE-2026-58063

A flaw was found in Bouncy Castle for Java. A remote attacker can exploit this vulnerability by providing a specially crafted BCFKS keystore file that specifies an unbounded Key Derivation Function (KDF) cost. This can lead to a Denial of Service (DoS) as the system attempts to process the file, consuming excessive resources and becoming unresponsive.

Bouncy Castle for Java is bundled as a cryptographic provider across numerous Red Hat products. Loading a BCFKS keystore honors an unbounded Key Derivation Function (KDF) cost from the untrusted file, so loading a crafted keystore forces excessive computation and a denial of service. Exploitation requires the application to load an attacker-supplied BCFKS keystore file. Note: Red Hat rates this Important (CVSS v3 7.5, A:H) versus the upstream CVEORG v4 score of 5.3 (Moderate, A:L).

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.

Red Hat is not aware of a mitigation for this flaw other than updating the affected Bouncy Castle component to a fixed version (bc-java 1.85, LTS 2.73.12, or BC-FJA bc-fips 1.0.2.7/2.0.2/2.1.3) once available for the affected product.