Writing
cryptography
2 articles on this subject.
Encrypted is not authenticated: padding oracles, ViewState, and why leaked machine keys became a 2025 problem
CBC without a MAC lets an attacker decrypt and forge ciphertext using nothing but the server's error behaviour. The mechanism from first principles, the Telerik and ASP.NET cases, and the one rule that removes the class.
7 min read
JWT: alg confusion, kid injection, and the day Java accepted a signature of zero
A JSON Web Token is only as good as the verification code. Five failure modes with concrete examples, including CVE-2022-21449, where an all-zero ECDSA signature validated against any key on Java 15 through 18.
8 min read