CVE-2026-63571 Attribute certificate path validation does not verify the attribute certificate's signature

Improper verification of cryptographic signature in the attribute certificate path validator PkixAttrCertPathValidator, also used by PkixAttrCertPathBuilder in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker to have a forged X.509 attribute certificate accepted as...

EUVD-2026-91221

Loop with unreachable exit condition in Pkcs12Store.GetCertificateChain in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a crafted PKCS12 file to an application that loads it and requests a key entry's certificate chain to cause a denial of service, in...

CVE-2026-63570

The bc-csharp library by Legion of the Bouncy Castle Inc. (versions before 2.7.0 ) is vulnerable to a denial of service (DoS) via an infinite loop in Pkcs12Store.GetCertificateChain . An attacker can provide a crafted PKCS#12 file containing certificates with cyclic issuer links —such as two cert...

CVE-2026-63570 Pkcs12Store.GetCertificateChain loops forever on cyclic issuer links

Loop with unreachable exit condition in Pkcs12Store.GetCertificateChain in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a crafted PKCS12 file to an application that loads it and requests a key entry's certificate chain to cause a denial of service, in...

CVE-2026-63569

The bc-csharp library by Legion of the Bouncy Castle Inc. (versions before 2.7.0 ) is vulnerable to improper input validation in the DHAgreement.CalculateAgreement function during MTI/A0 two-pass Diffie-Hellman key exchanges. An on-path attacker can provide a crafted out-of-range or small-order e...

CVE-2026-63569 MTI/A0 DHAgreement does not validate the peer's ephemeral value

Improper input validation in DHAgreement.CalculateAgreement MTI/A0 two-pass Diffie-Hellman in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an on-path attacker to make the local party compute an agreed value the attacker already knows, defeating the key authentication MTI/A0 is...

EUVD-2026-91220

Improper input validation in DHAgreement.CalculateAgreement MTI/A0 two-pass Diffie-Hellman in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an on-path attacker to make the local party compute an agreed value the attacker already knows, defeating the key authentication MTI/A0 is...

EUVD-2026-91219

Allocation of resources without limits or throttling in the CMP/CRMF password-based MAC verifier PKMacBuilder in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a CMP message or CRMF certifica...

CVE-2026-63568

The Bouncy Castle Inc. bc-csharp library (versions before 2.7.0 ) is vulnerable to a denial of service via CPU exhaustion. The flaw exists in the PKMacBuilder component, which handles CMP/CRMF password-based MAC verification. Specifically, the ProtectedPkiMessage.Verify and CertificateRequestMess...

CVE-2026-63568 Unbounded CMP/CRMF password-based MAC iteration count allows CPU exhaustion

Allocation of resources without limits or throttling in the CMP/CRMF password-based MAC verifier PKMacBuilder in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a CMP message or CRMF certifica...

CVE-2026-63568 Unbounded CMP/CRMF password-based MAC iteration count allows CPU exhaustion

Allocation of resources without limits or throttling in the CMP/CRMF password-based MAC verifier PKMacBuilder in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a CMP message or CRMF certifica...

CVE-2026-63567

The bc-csharp library by Bouncy Castle Inc. is vulnerable in versions before 2.7.0 due to an observable discrepancy in IesEngine.DecryptBlock. In block-cipher mode, the engine decrypts the ciphertext and removes padding before verifying the MAC. This allows a remote attacker to perform a CBC padd...

EUVD-2026-91218

Observable discrepancy in IesEngine.DecryptBlock in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has captured an IES or ECIES ciphertext, and who can submit modified ciphertexts for decryption under the same key pair, to recover its plaintext via a CBC...

CVE-2026-63567 IesEngine block-cipher mode checks padding before MAC (CBC padding oracle)

Observable discrepancy in IesEngine.DecryptBlock in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has captured an IES or ECIES ciphertext, and who can submit modified ciphertexts for decryption under the same key pair, to recover its plaintext via a CBC...

EUVD-2026-91217

Memory allocation with excessive size value in the DTLS handshake reassembly DtlsReliableHandshake, DtlsReassembler in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated DTLS peer to cause a denial of service through memory exhaustion via crafted handshake...

CVE-2026-63566 DTLS handshake reassembler allocates buffer from unchecked 24-bit length

Memory allocation with excessive size value in the DTLS handshake reassembly DtlsReliableHandshake, DtlsReassembler in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated DTLS peer to cause a denial of service through memory exhaustion via crafted handshake...

CVE-2026-63566 DTLS handshake reassembler allocates buffer from unchecked 24-bit length

Memory allocation with excessive size value in the DTLS handshake reassembly DtlsReliableHandshake, DtlsReassembler in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated DTLS peer to cause a denial of service through memory exhaustion via crafted handshake...

CVE-2026-63566

The bc-csharp library (versions before 2.7.0 ) by Legion of the Bouncy Castle Inc. is vulnerable to a memory exhaustion denial of service. The flaw exists in the DTLS handshake reassembly (DtlsReliableHandshake , DtlsReassembler ), where the system allocates a reassembly buffer based on a 24-bit ...

CVE-2026-16001 IesEngine stream-mode MAC forgery via length-dependent KDF split

Exposure of the message authentication key through the encryption keystream in the stream mode of IesEngine an IesEngine constructed without a block cipher in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has observed one encrypted message with known plainte...

EUVD-2026-91206

Exposure of the message authentication key through the encryption keystream in the stream mode of IesEngine an IesEngine constructed without a block cipher in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has observed one encrypted message with known plainte...