CVE-2020-8929

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 v3 5.3 MEDIUM
CVSS v2.0 5.0 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:P/A:N

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899	Patch Third Party Advisory
https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r	Patch Third Party Advisory
https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899	Patch Third Party Advisory
https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:google:tink_java:*:*:*:*:*:*:*:*

History

05 Jun 2025, 14:50

Type	Values Removed	Values Added
CPE	cpe:2.3:a:google:tink::::::::	cpe:2.3:a:google:tink_java::::::::
First Time		Google tink Java

Information

Published : 2020-10-19 13:15

Updated : 2025-06-05 14:50

NVD link : CVE-2020-8929

Mitre link : CVE-2020-8929

CVE.ORG link : CVE-2020-8929

JSON object : View

Products Affected

google

tink_java

CWE

CWE-176

Improper Handling of Unicode Encoding

NVD-CWE-Other

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