Advisories for Pypi/Jwcrypto package

Affected version Vendor: https://github.com/latchset/jwcrypto Version: 1.5.5 Description An attacker can cause a DoS attack by passing in a malicious JWE Token with a high compression ratio. When the server processes this Token, it will consume a lot of memory and processing time. Poc from jwcrypto import jwk, jwe from jwcrypto.common import json_encode, json_decode import time public_key = jwk.JWK() private_key = jwk.JWK.generate(kty='RSA', size=2048) public_key.import_key(**json_decode(private_key.export_public())) payload = '{"u": "' + "u" * …

Impact Denial of Service, Applications that allow the use of the PBKDF2 algorithm. Patches A patch is available that sets the maximum number of default rounds. Workarounds Applications that do not need to use PBKDF2 should simply specify the algorithms use and exclude it from the list. Applications that need to use the algorithm should upgrade to the new version that allows to set a maximum rounds number. Acknowledgement The …

The JWT code can auto-detect the type of token being provided, and this can lead the application to incorrect conclusions about the trustworthiness of the token. Quoting the private disclosure we received : "Under certain circumstances, it is possible to substitute a [..] signed JWS with a JWE that is encrypted with the public key that is normally used for signature validation." This substitution attack can occur only if the …