Executive brief
Bouncy Castle, a widely used Java library for encryption and secure communications, contains a flaw in its FIPS-compliant Java API. On specific Linux systems using modern Intel processors, certain encryption operations may fail or behave inconsistently. This can lead to service disruptions or application errors when processing encrypted data, potentially impacting the reliability of secure business transactions.
Technical details
A vulnerability exists in the Legion of the Bouncy Castle BC-FJA BC-FIPS library (versions 2.1.0 through 2.1.2) specifically within the gcm128w and gcm512w program files. The issue is classified as CWE-1068 (Inconsistency Between Implementation and Documented Design) and affects Linux environments on X86_64 architecture utilizing AVX and AVX-512f instruction sets. The flaw involves GCM chunking which can lead to 'bad tag' exceptions during decryption. An attacker with local access could potentially trigger these inconsistencies to cause a denial-of-service (availability impact) by forcing decryption failures. No patch is explicitly detailed in the primary advisory, though related LTS versions (BC-LTS) fixed similar behavior in version 2.73.11.
Affected products
- Legion of the Bouncy Castle BC-FJA BC-FIPS (bc-fips) 2.1.0 - 2.1.2
Timeline
- 2026-05-08: disclosed
- 2026-05-08: advisory: Published to GitHub Advisory Database and NVD