CVE-2025-54887 — Vulnerability in jwe — CVE Details

### Overview The authentication tag of encrypted JWEs can be brute forced, which may result in loss of confidentiality for those JWEs and provide ways to craft arbitrary JWEs. ### Impact - JWEs can be modified to decrypt to an arbitrary value - JWEs can be decrypted by observing parsing differences - The GCM internal [GHASH key](https://en.wikipedia.org/wiki/Galois/Counter_Mode#:~:text=\)%20is%20the-,hash%20key,-%2C%20a%20string%20of) can be recovered ### Am I Affected? You are affected by this vulnerability even if you do not use an `AES-GCM` encryption algorithm for your JWEs. ### Patches The version 1.1.1 fixes the issue by adding the tag length check for the `AES-GCM` algorithm. **Important:** As the [GHASH key](https://en.wikipedia.org/wiki/Galois/Counter_Mode#:~:text=\)%20is%20the-,hash%20key,-%2C%20a%20string%20of) could have leaked, you must rotate the encryption keys after upgrading to version 1.1.1. ### References [Félix Charette talk at NorthSec 2025 about the issue](https://www.youtube.com/watch?v=9IT659uUXfs&t=15830s)