CVE-2020-8929 Information

Description

A mis-handling of invalid unicode characters in the Java implementation of Tink versions prior to 1.5 allows an attacker to change the ID part of a ciphertext which result in the creation of a second ciphertext that can decrypt to the same plaintext. This can be a problem with encrypting deterministic AEAD with a single key and rely on a unique ciphertext-per-plaintext.

CVSS Vector

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

Reference

https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899 https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

LOW

Base Score

NONE

Base Severity

5.3