CVE-2026-15055

A flaw was found in Bouncy Castle for Java. An attacker could exploit this vulnerability by providing a specially crafted input to the PKCS#8 / PBES2 decryptors. This input could specify an excessively high Key Derivation Function (KDF) cost, causing the decryptor to consume significant computational resources. This resource exhaustion can lead to a denial of service (DoS), making the affected system unresponsive or unavailable.

Bouncy Castle for Java is bundled as a cryptographic provider across numerous Red Hat products. The PKCS#8 / PBES2 decryptors honor an unbounded Key Derivation Function (KDF) cost supplied in the input, so a crafted PKCS#8/PBES2 blob forces excessive computation and a denial of service. Exploitation requires the application to decrypt attacker-supplied PKCS#8/PBES2 data. 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 bcpkix-fips 1.0.12/2.0.12/2.1.12) once available for the affected product.