CVE-2026-18036

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-63570

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...

DEBIAN-CVE-2026-17507

In Bouncy Castle for Java before 1.86, the MLS implementation org.bouncycastle.mls holds RFC 9420's uint32 leafindex in a signed int, so a wire value with the top bit set decodes to a negative number. That is a legitimate encoding rather than malformed input, and it must still decode, since the M...

CVE-2026-63571

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...

DEBIAN-CVE-2026-17508

In Bouncy Castle for Java before 1.86, several password-based key derivation entry points ran the KDF with cost parameters taken from the untrusted input being processed, without bounding them, so a small input could dictate an arbitrary amount of work before any password or integrity check could...

DEBIAN-CVE-2026-18036

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

UBUNTU-CVE-2026-17508

In Bouncy Castle for Java before 1.86, several password-based key derivation entry points ran the KDF with cost parameters taken from the untrusted input being processed, without bounding them, so a small input could dictate an arbitrary amount of work before any password or integrity check could...

UBUNTU-CVE-2026-18036

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-103600

Uncontrolled recursion in the ASN.1 parser Asn1InputStream, Asn1StreamParser in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service via a crafted ASN.1 encoding of deeply nested constructed elements for example SEQUENCE...

CVE-2026-103603

Memory allocation with excessive size value in the HSS/LMS signature code HssPublicKeyParameters, HssSignature in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker who can supply both an HSS public key and a signature to cause a denial of service...

CVE-2026-103601

Release of unverified plaintext in the CCM CcmBlockCipher and DSTU 7624 CCM KCcmBlockCipher AEAD modes in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker to obtain decryptions of ciphertexts of their choosing via forged messages sent to an application that lets th...

CVE-2026-103602

Improper certificate validation in PkixNameConstraintValidator in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who controls, or can obtain certificates from, a name-constrained intermediate CA to have certificates accepted during PKIX certification path validation fo...

CVE-2026-103604

Inefficient algorithmic complexity in X.509 distinguished name string conversion X509Name.ToString and IetfUtilities.ValueToString 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...

UBUNTU-CVE-2026-17507

In Bouncy Castle for Java before 1.86, the MLS implementation org.bouncycastle.mls holds RFC 9420's uint32 leafindex in a signed int, so a wire value with the top bit set decodes to a negative number. That is a legitimate encoding rather than malformed input, and it must still decode, since the M...

EUVD-2026-91317

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-18036

Bouncy Castle for Java versions prior to 1.86 are vulnerable to a timing side-channel attack in the NTRU implementation. The root cause is the use of the % operator in three helpers, leading to integer division where latency depends on the secret operand. Specifically, Polynomial.modQ divides by ...

CVE-2026-18036 NTRU leaks private key information by reducing secret values with a non-constant-time integer division

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-18036 NTRU leaks private key information by reducing secret values with a non-constant-time integer division

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-18036

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...

CVE-2026-18036 NTRU leaks private key information by reducing secret values with a non-constant-time integer division

In Bouncy Castle for Java before 1.86, NTRU reduced secret values with the % operator in three helpers whose reference implementations are deliberately division-free, so each reduction was carried out by an integer division whose latency depends on the secret operand. Polynomial.modQ divided by a...