python-jose through 3.5.0 Authentication Bypass via Empty HMAC Key

python-jose through 3.5.0 contains an authentication bypass vulnerability that allows unauthenticated attackers to forge JWTs because HMACKey and CryptographyHMACKey accept zero-length HMAC secrets. When an application's HS256/HS384/HS512 verification key resolves to empty, such as an oct JWK with empty k, attackers can forge tokens with arbitrary claims that jwt.decode accepts.

python-jose: python-jose: Denial-of-Service via malicious JSON Web Encryption (JWE) token decompression

In python-jose 3.3.0 (specifically jwe.decrypt), a vulnerability allows an attacker to cause a Denial-of-Service (DoS) condition by crafting a malicious JSON Web Encryption (JWE) token with an exceptionally high compression ratio. When this token is processed by the server, it results in significant memory allocation and processing time during decompression.

python-jose through 3.5.0 Algorithm Confusion via DER-encoded Public Key as HMAC Secret

python-jose through 3.5.0 fails to properly validate asymmetric keys in HMAC initialization, accepting DER-encoded public keys that lack PEM armor or SSH prefixes. Attackers holding the service's public key can forge HS256 tokens that pass verification when algorithms are not explicitly restricted. This is an incomplete fix for CVE-2024-33663.

python-jose: algorithm confusion with OpenSSH ECDSA keys and other key formats

python-jose through 3.3.0 has algorithm confusion with OpenSSH ECDSA keys and other key formats. This is similar to CVE-2022-29217.

python-jose: allows attackers to cause a denial of service

python-jose through 3.3.0 allows attackers to cause a denial of service (resource consumption) during a decode via a crafted JSON Web Encryption (JWE) token with a high compression ratio, aka a "JWT bomb." This is similar to CVE-2024-21319.

python-jose before 1.3.2 allows attackers to have unspecified impact by leveraging failure to use a constant time comparison for HMAC keys.