Tink Android
Monthly
MAC tag forgery in Google Tink (tink-java and tink-android) is enabled by a non-constant-time comparison in the ChunkedMacVerification object, which leaks per-byte matching progress through response-timing differences. An attacker who can submit many verification attempts and measure timing can reconstruct a valid MAC tag byte-by-byte, defeating the integrity/authenticity guarantee the MAC is meant to provide. Reported by Google and tracked in tink-java issue #75; no public exploit identified at time of analysis, and the CVSS 4.0 score is 8.2 driven entirely by integrity impact.
MAC tag forgery in Google Tink (tink-java and tink-android) is enabled by a non-constant-time comparison in the ChunkedMacVerification object, which leaks per-byte matching progress through response-timing differences. An attacker who can submit many verification attempts and measure timing can reconstruct a valid MAC tag byte-by-byte, defeating the integrity/authenticity guarantee the MAC is meant to provide. Reported by Google and tracked in tink-java issue #75; no public exploit identified at time of analysis, and the CVSS 4.0 score is 8.2 driven entirely by integrity impact.