{"cve":"CVE-2020-8929","nvd":{"published":"2020-10-19T13:15:13.437","modified":"2026-06-17T03:27:11.487","status":"Analyzed","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","score":5.3},"cwes":["CWE-176"],"references":["https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899","https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r","https://github.com/google/tink/commit/93d839a5865b9d950dffdc9d0bc99b71280a8899","https://github.com/google/tink/security/advisories/GHSA-g5vf-v6wf-7w2r"],"products":["google:tink_java"],"source":"nvd","synced_at":"2026-10-19T21:09:53.489947993+00:00"},"epss":{"cve":"CVE-2020-8929","score":0.00463,"percentile":0.40148,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-g5vf-v6wf-7w2r","url":"https://osv.dev/vulnerability/GHSA-g5vf-v6wf-7w2r","summary":"Ciphertext Malleability Issue in Tink Java","modified":"2026-07-08T06:00:03.145975600Z","packages":[{"ecosystem":"Maven","name":"com.google.crypto.tink:tink","purl":"pkg:maven/com.google.crypto.tink/tink","ranges":["<1.5.0"],"fixed":["1.5.0"]}]},{"id":"PYSEC-2020-142","url":"https://osv.dev/vulnerability/PYSEC-2020-142","summary":"","modified":"2023-11-08T04:04:19.465376Z","packages":[{"ecosystem":"PyPI","name":"tink","purl":"pkg:pypi/tink","ranges":["<1.5.0"],"fixed":["1.5.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}