CVE-2020-8929
CVE-2020-8929 is a medium-severity vulnerability in Google Tink Java with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-176.
Key facts
- Severity: Medium (CVSS 3.x base score 5.3)
- CVSS v2: 5.0
- EPSS exploit prediction: 0% (37th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-176
- Affected product: Google Tink Java
- Published:
- Last modified:
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.
Frequently asked questions
- What is 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.
- How severe is CVE-2020-8929?
- CVE-2020-8929 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
- Is CVE-2020-8929 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-8929?
- CVE-2020-8929 affects Google Tink Java. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-8929?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-8929 published?
- CVE-2020-8929 was published on 2020-10-19 and last updated on 2026-06-17.
References
- https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899
- https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r
Affected products (1)
- cpe:2.3:a:google:tink_java:*:*:*:*:*:*:*:*
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