Vulnerability: Cryptographic Security Weakening and Denial of Service in Noise Protocol Implementation

CVE-2021-4239 · HIGH Severity

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

The Noise protocol implementation suffers from weakened cryptographic security after encrypting 2^64 messages, and a potential denial of service attack. After 2^64 (~18.4 quintillion) messages are encrypted with the Encrypt function, the nonce counter will wrap around, causing multiple messages to be encrypted with the same key and nonce. In a separate issue, the Decrypt function increments the nonce state even when it fails to decrypt a message. If an attacker can provide an invalid input to the Decrypt function, this will cause the nonce state to desynchronize between the peers, resulting in a failure to encrypt all subsequent messages.

Learn more about our Web Application Penetration Testing UK.