{"id":"DEBIAN-CVE-2026-48998","details":"guzzlehttp/psr7 is a PSR-7 HTTP message library implementation in PHP. Versions prior to 2.10.2 contain improper Host header validation when parsing raw HTTP request messages and when deriving a server request URI from server variables. An attacker can provide a malformed Host header containing URI authority delimiters, such as `trusted.example@evil.example`. When the Host value is used to construct a URI, the malformed value can be reinterpreted as URI userinfo and host. This can cause the PSR-7 request URI host to differ from the original Host header value. Applications are affected if they parse attacker-controlled raw HTTP requests with `GuzzleHttp\\Psr7\\Message::parseRequest()` or the legacy 1.x `GuzzleHttp\\Psr7\\parse_request()` function, or if they build server requests from attacker-controlled server variables, then rely on the resulting URI host for routing, allow-list checks, or forwarding decisions. In affected forwarding or gateway scenarios, this may cause requests or credentials to be sent to an unintended host. The issue is patched in `2.10.2`. `1.x` is end-of-life and will not receive a patch. Some workarounds are available. Validate the `Host` header as `uri-host [ \":\" port ]` before calling `Message::parseRequest()` or legacy `parse_request()` on untrusted HTTP request data, or before deriving routing and forwarding decisions from a parsed request URI. Reject Host values containing userinfo, path, query, or fragment delimiters.","modified":"2026-09-01T16:06:48.238444341Z","published":"2026-06-11T13:16:33.133Z","upstream":["CVE-2026-48998"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-48998"}],"affected":[{"package":{"name":"php-guzzlehttp-psr7","ecosystem":"Debian:12","purl":"pkg:deb/debian/php-guzzlehttp-psr7?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.4.5-1+deb12u1"}]}],"versions":["2.4.5-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48998.json"}},{"package":{"name":"php-guzzlehttp-psr7","ecosystem":"Debian:13","purl":"pkg:deb/debian/php-guzzlehttp-psr7?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.7.1-1+deb13u1"}]}],"versions":["2.7.1-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48998.json"}},{"package":{"name":"php-guzzlehttp-psr7","ecosystem":"Debian:14","purl":"pkg:deb/debian/php-guzzlehttp-psr7?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.10.3-1"}]}],"versions":["2.7.1-1","2.8.0-1","2.8.0-2","2.9.0-1","2.9.0-2"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48998.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"}]}