{"id":"CVE-2026-42327","aliases":["GHSA-xp3w-r5p5-63rr"],"url":"https://o3.security/vulnerability/CVE-2026-42327","summary":"rust-openssl: undefined behavior in X509Ref::ocsp_responders for certificates with non-UTF-8 OCSP URLs","details":"rust-openssl provides OpenSSL bindings for the Rust programming language. From 0.9.7 to before 0.10.79, X509Ref::ocsp_responders returns OCSP responder URLs from a certificate's AIA extension as OpensslString, whose Deref<Target = str> wraps the raw bytes with str::from_utf8_unchecked. OpenSSL does not enforce that the underlying IA5String is ASCII, so a certificate with non-UTF-8 bytes in its OCSP accessLocation causes safe Rust code to construct a &str that violates the UTF-8 invariant — resulting in undefined behavior. This vulnerability is fixed in 0.10.79.","published":"2026-05-14T20:17:39.923Z","modified":"2026-08-07T11:49:54.030268370Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"crates.io","name":"openssl","fixedVersion":"0.10.79"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42327.json"},{"type":"ADVISORY","url":"https://github.com/rust-openssl/rust-openssl/security/advisories/GHSA-xp3w-r5p5-63rr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42327"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:49:54.030268370Z"}}