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 inside SEQUENCE, in definite-length DER or indefinite-length BER form), because each nesting level is parsed by a further recursive call with no bound on depth. About 2,000 levels (8 KB of DER) are enough to exhaust a 1.5 MB thread stack, the .NET main-thread default on Windows, and raise a StackOverflowException, which .NET cannot catch and which terminates the whole process; on threads with larger stacks, parse time instead grows quadratically with depth (about 9 seconds of CPU for a 64 KB input). Any path that parses untrusted ASN.1 is exposed, including X.509 certificates and CRLs, CMS/PKCS#7, PKCS#8/PKCS#12, OCSP and TLS Certificate messages.

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 through memory exhaustion via a public key encoding with an excessive level count, because the level count L read when parsing an HSS public key was not checked against the RFC 8554 maximum of 8, and signature parsing then allocated an array of L - 1 entries before reading any further signature data. A single verification can commit up to about 17 GB of memory or fail with an OutOfMemoryException.

Loop with unreachable exit condition in the PKCS#12 key derivation (Pkcs12ParametersGenerator) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a PKCS#12 (PFX) file, or a PKCS#8 encrypted private key that uses a PKCS#12 password-based encryption algorithm, to cause a denial of service through CPU exhaustion via an iteration count of zero or below, because the derivation loop ran until its counter equalled the count, so for such a count it wrapped through about 2^32 iterations before the MAC or the password could be checked. A 75-byte PFX file with a negative MacData iteration count kept Pkcs12Store.Load busy for many minutes.

Uncontrolled Resource Consumption vulnerability in Legion of the Bouncy Castle Inc. Bouncy Castle for Java FIPS bc-fips on All (API modules), Legion of the Bouncy Castle Inc. Bouncy Castle for Java LTS bcprov-lts8on on All (API modules) allows Excessive Allocation. This vulnerability is associated with program files core/src/main/jdk1.9/org/bouncycastle/crypto/fips/AESNativeCFB.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/fips/AESNativeGCM.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/fips/SHA256NativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/fips/AESNativeEngine.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/fips/AESNativeCBC.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/fips/AESNativeCTR.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeCFB.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeGCM.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeEngine.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeCBC.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeGCMSIV.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeCCM.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/engines/AESNativeCTR.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHA256NativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHA224NativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHA3NativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHAKENativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHA512NativeDigest.Java, core/src/main/jdk1.9/org/bouncycastle/crypto/digests/SHA384NativeDigest.Java.

This issue affects Bouncy Castle for Java FIPS: from 2.1.0 through 2.1.1; Bouncy Castle for Java LTS: from 2.73.0 through 2.73.7.