CVE-2026-71891 BLS12-381 key validation accepts a public key built on a foreign curve

In Bouncy Castle for Java before 1.86, BLS12381BasicScheme.keyValidate, and so BLSPublicKeyParameters and every BasicScheme, MessageAugmentation and ProofOfPossession verify and aggregateVerify that gate on it, accepted a public key built on a foreign ECCurve that merely shares BLS12-381's field...

CVE-2026-71891

In Bouncy Castle for Java before 1.86, BLS12381BasicScheme.keyValidate, and so BLSPublicKeyParameters and every BasicScheme, MessageAugmentation and ProofOfPossession verify and aggregateVerify that gate on it, accepted a public key built on a foreign ECCurve that merely shares BLS12-381's field...

CVE-2026-71891

In Bouncy Castle for Java before 1.86, BLS12381BasicScheme.keyValidate, and so BLSPublicKeyParameters and every BasicScheme, MessageAugmentation and ProofOfPossession verify and aggregateVerify that gate on it, accepted a public key built on a foreign ECCurve that merely shares BLS12-381's field...

CVE-2026-71891

In Bouncy Castle for Java before version 1.86 , the BLS12_381BasicScheme.keyValidate function (and associated components like BLSPublicKeyParameters) failed to properly validate public keys. It accepted keys built on a foreign ECCurve that shared the same field characteristic as BLS12-381 . The r...

CVE-2026-18040 HQC leaks private key information through secret-indexed GF(2^8) tables and a secret-dependent fixed-weight sampler

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-18040

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-18040 HQC leaks private key information through secret-indexed GF(2^8) tables and a secret-dependent fixed-weight sampler

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-18040

Bouncy Castle for Java versions before 1.86 are vulnerable to the leakage of secret-derived data within the HQC implementation. The root cause involves two side channels: GF(2^8) arithmetic utilizing lookup tables indexed by field elements (making touched cache lines a function of the operand), a...

EUVD-2026-92004

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-18040 HQC leaks private key information through secret-indexed GF(2^8) tables and a secret-dependent fixed-weight sampler

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-18040

In Bouncy Castle for Java before 1.86, HQC leaked secret-derived data through two side channels: its GF2^8 arithmetic used lookup tables indexed by field elements, making the cache line touched a function of the operand, and its fixed-weight support sampler left its duplicate scan as soon as a...

CVE-2026-71885 MLS X.509 credential not bound to the LeafNode signature key

In Bouncy Castle for Java before 1.86, the Messaging Layer Security MLS, RFC 9420 implementation did not bind an X.509 credential to a LeafNode's signaturekey. LeafNode.verify checked a leaf's signature against the signaturekey carried in the leaf itself, while the credential's X.509 certificate...

CVE-2026-71885 MLS X.509 credential not bound to the LeafNode signature key

In Bouncy Castle for Java before 1.86, the Messaging Layer Security MLS, RFC 9420 implementation did not bind an X.509 credential to a LeafNode's signaturekey. LeafNode.verify checked a leaf's signature against the signaturekey carried in the leaf itself, while the credential's X.509 certificate...

CVE-2026-71885

In Bouncy Castle for Java versions before 1.86 , the Messaging Layer Security (MLS, RFC 9420) implementation failed to bind an X.509 credential to a LeafNode's signature_key . Because the X.509 certificate chain was stored but never parsed or validated, the end-entity certificate's public key was...

EUVD-2026-92003

In Bouncy Castle for Java before 1.86, the Messaging Layer Security MLS, RFC 9420 implementation did not bind an X.509 credential to a LeafNode's signaturekey. LeafNode.verify checked a leaf's signature against the signaturekey carried in the leaf itself, while the credential's X.509 certificate...

CVE-2026-71885 MLS X.509 credential not bound to the LeafNode signature key

In Bouncy Castle for Java before 1.86, the Messaging Layer Security MLS, RFC 9420 implementation did not bind an X.509 credential to a LeafNode's signaturekey. LeafNode.verify checked a leaf's signature against the signaturekey carried in the leaf itself, while the credential's X.509 certificate...

CVE-2026-71885

In Bouncy Castle for Java before 1.86, the Messaging Layer Security MLS, RFC 9420 implementation did not bind an X.509 credential to a LeafNode's signaturekey. LeafNode.verify checked a leaf's signature against the signaturekey carried in the leaf itself, while the credential's X.509 certificate...

CVE-2026-71886 OpenPGP certification accepted from a subkey without certification authority

In Bouncy Castle for Java before 1.86, the high-level OpenPGP certificate API accepted a third-party certification or trust delegation from any component key of the issuing certificate, without requiring that component to have been granted the authority to certify...

CVE-2026-71886

In Bouncy Castle for Java before 1.86, the high-level OpenPGP certificate API accepted a third-party certification or trust delegation from any component key of the issuing certificate, without requiring that component to have been granted the authority to certify...

EUVD-2026-92002

In Bouncy Castle for Java before 1.86, the high-level OpenPGP certificate API accepted a third-party certification or trust delegation from any component key of the issuing certificate, without requiring that component to have been granted the authority to certify...