{"id":"CVE-2026-59882","aliases":["GHSA-c2w2-prh8-qm98"],"url":"https://o3.security/vulnerability/CVE-2026-59882","summary":"guzzlehttp/psr7: Host Confusion via Weak URI Host Validation","details":"guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Prior to 2.12.3, Uri::assertValidHost() does not reject URI host components containing authority delimiters, embedded ports, or malformed IPv6 brackets, allowing Uri::getHost() to disagree with the URI authority used for security or routing decisions. This issue is fixed in version 2.12.3.","published":"2026-07-08T15:50:03.077Z","modified":"2026-08-12T03:51:46.213152456Z","cvss":{"score":4.2,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N"},"epss":{"score":0.00317,"percentile":0.24262,"asOf":"2026-09-07"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"guzzlehttp/psr7","fixedVersion":"2.12.3"}],"fix":{"url":"https://github.com/guzzle/psr7/commit/ddd64f17d4cc1f7e5ffe6fd2c989ec7221712580","label":"guzzle/psr7@ddd64f1"},"references":[{"type":"WEB","url":"https://github.com/guzzle/psr7/releases/tag/2.12.3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59882.json"},{"type":"ADVISORY","url":"https://github.com/guzzle/psr7/security/advisories/GHSA-c2w2-prh8-qm98"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59882"},{"type":"FIX","url":"https://github.com/guzzle/psr7/commit/ddd64f17d4cc1f7e5ffe6fd2c989ec7221712580"},{"type":"FIX","url":"https://github.com/guzzle/psr7/pull/811"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:46.213152456Z"}}