{"answers":{"affected":"3 open source packages ship an affected version, including com.google.crypto.tink:tink and tink. It affects 1 product.","exploited":"There is no known exploitation of CVE-2020-8929 in the wild and no public exploit code.","fix":"Upgrade com.google.crypto.tink:tink to 1.5.0 or later.","what":"CVE-2020-8929 is a medium-severity vulnerability in Google LLC Tink, published on 19 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2020-8929 and fix it if it is affected.\n\nWhat it is: CVE-2020-8929 is a medium-severity vulnerability in Google LLC Tink, published on 19 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2020-8929 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- com.google.crypto.tink:tink (Maven): affected all versions; fixed in 1.5.0\n- com.google.crypto.tink:tink (Maven): affected all versions; fixed in 1.5.0\n- tink (PyPI): affected all versions; fixed in 1.5.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2020-8929/ (Markdown: https://insights.sbomify.com/CVE-2020-8929/index.md)","id":"CVE-2020-8929","markdown":"https://insights.sbomify.com/CVE-2020-8929/index.md","name":"CVE-2020-8929","record":{"aliases":["GHSA-g5vf-v6wf-7w2r","PYSEC-2020-142"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_modify"],"network_reachable":"yes","non_default_config":false,"product_category":"Java cryptography library","requires_auth":"none","summary":"Attackers can modify ciphertext IDs to create duplicates decrypting to the same plaintext, compromising integrity in deterministic AEAD scenarios.","user_interaction":"not_required","vuln_class":"weak_cryptography"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Google","cpe":[{"product":"tink_java","vendor":"google"}],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-176","name":"Improper Handling of Unicode Encoding"}],"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.","ecosystems":["Maven","PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Ciphertext integrity weakness in Tink","id":"CVE-2020-8929","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Maven","product":null,"products":[],"type":"weak_cryptography","year":"2020"},"n_packages":3,"n_references":2,"next":{"headline":"Priviged Escalation in Google Cloud Platform's Guest-OSLogin","id":"CVE-2020-8933"},"packages":[{"ecosystem":"Maven","fixed":["1.5.0"],"introduced":["0"],"last_affected":[],"package":"com.google.crypto.tink:tink","purl":null,"source":"GHSA-g5vf-v6wf-7w2r"},{"ecosystem":"Maven","fixed":["1.5.0"],"introduced":["0"],"last_affected":[],"package":"com.google.crypto.tink:tink","purl":"pkg:maven/com.google.crypto.tink/tink","source":"GHSA-g5vf-v6wf-7w2r"},{"ecosystem":"PyPI","fixed":["1.5.0"],"introduced":["0"],"last_affected":[],"package":"tink","purl":"pkg:pypi/tink","source":"PYSEC-2020-142"}],"prev":{"headline":"Buffer overflow in Brotli library","id":"CVE-2020-8927"},"products":["Tink"],"published":"2020-10-19","related":[{"cvss_score":8.2,"headline":"Observable Timing Discrepancy in Tink-Java and Tink-Android ChunkedMacVerification","id":"CVE-2026-15432","kev_date_added":null,"published":"2026-07-21"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-04","vendors":["Google LLC"]},"summary":"Attackers can modify ciphertext IDs to create duplicates decrypting to the same plaintext, compromising integrity in deterministic AEAD scenarios.","url":"https://insights.sbomify.com/CVE-2020-8929/"}