CVE-2025-13470 — Use of Insufficiently Random Values in RNP

In RNP version 0.18.0 a refactoring regression causes the symmetric session key used for Public-Key Encrypted Session Key (PKESK) packets to be left uninitialized except for zeroing, resulting in it always being an all-zero byte array. Any data encrypted using public-key encryption in this release can be decrypted trivially by supplying an all-zero session key, fully compromising confidentiality. The vulnerability affects only public key encryption (PKESK packets). Passphrase-based encryption …