{"id":"JLSEC-2026-693","summary":"ML-KEM-1024 x64 AVX2 implicit rejection failure in the Fujisaki-Okamoto transform breaks IND-CCA2...","details":"wolfSSL's AVX2-optimized ML-KEM implementation (mlkem_cmp_avx2) compares only 1536 of the 1568 ciphertext bytes during the Fujisaki-Okamoto re-encryption check in ML-KEM-1024 decapsulation. Ciphertexts that differ from the expected re-encryption solely in bytes 1536-1567 bypass implicit rejection and are accepted as valid, breaking IND-CCA2 security. An attacker able to submit chosen ciphertexts to a decapsulation oracle that uses a static ML-KEM-1024 key, and to observe whether the genuine shared secret or the implicit-rejection secret was produced, can use this as a plaintext-checking oracle to recover the private key. A proof of concept recovered a full ML-KEM-1024 private key with approximately 98% success using roughly 350 chosen ciphertexts. The flaw is a deterministic logic error and does not rely on timing measurements.","modified":"2026-07-14T21:50:15.441589033Z","published":"2026-07-14T21:41:35.775Z","upstream":["CVE-2026-10097","EUVD-2026-39553","GHSA-hcgc-hfp6-58v4"],"database_specific":{"license":"CC-BY-4.0","sources":[{"modified":"2026-06-26T17:16:31.693Z","published":"2026-06-25T20:17:09.160Z","url":"https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-10097","html_url":"https://nvd.nist.gov/vuln/detail/CVE-2026-10097","database_specific":{"status":"Modified"},"id":"CVE-2026-10097","imported":"2026-07-14T21:22:49.547Z"},{"imported":"2026-07-14T21:22:58.060Z","modified":"2026-06-26T18:34:51Z","published":"2026-06-25T21:31:30Z","url":"https://api.github.com/advisories/GHSA-hcgc-hfp6-58v4","html_url":"https://github.com/advisories/GHSA-hcgc-hfp6-58v4","id":"GHSA-hcgc-hfp6-58v4"},{"url":"https://euvdservices.enisa.europa.eu/api/enisaid?id=EUVD-2026-39553","html_url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-39553","id":"EUVD-2026-39553","imported":"2026-07-14T21:22:51.069Z","modified":"2026-06-26T16:35:41Z","published":"2026-06-25T19:59:30Z"}]},"references":[{"type":"WEB","url":"https://github.com/advisories/GHSA-hcgc-hfp6-58v4"},{"type":"WEB","url":"https://github.com/wolfSSL/wolfssl/pull/10430"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-10097"},{"type":"WEB","url":"https://www.wolfssl.com/docs/security-vulnerabilities"},{"type":"WEB","url":"https://www.wolfssl.com/docs/security-vulnerabilities/"}],"affected":[{"package":{"name":"wolfSSL_jll","ecosystem":"Julia","purl":"pkg:julia/wolfSSL_jll?uuid=98c43586-9870-5ae5-ab22-acc77b9bbdb5"},"ranges":[{"type":"SEMVER","events":[{"introduced":"5.7.2+0"},{"fixed":"5.9.2+0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2026/JLSEC-2026-693.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"}]}