{"id":"CVE-2025-14523","title":"A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing","summary":"A flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost con…","severity":"high","cvss":8.2,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","cwe":["CWE-444"],"published":"2025-12-11","updated":"2026-06-25","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-14523","references":[{"url":"https://access.redhat.com/errata/RHSA-2026:0421","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0422","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0423","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0836","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0867","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0868","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0905","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0906","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0907","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0908","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0909","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0911","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:0925","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:1509","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:1569","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:1570","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:1571","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:1572","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2025-14523","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2421349","label":"secalert@redhat.com"},{"url":"https://gitlab.gnome.org/GNOME/libsoup/-/issues/472","label":"secalert@redhat.com"}],"tags":["nvd"],"epss":0.00544,"epssPercentile":0.44544,"ingestedAt":"2026-06-29T13:24:34.621Z","slug":"CVE-2025-14523","body":"## Overview\n\nA flaw in libsoup’s HTTP header handling allows multiple Host: headers in a request and returns the last occurrence for server-side processing. Common front proxies often honor the first Host: header, so this mismatch can cause vhost confusion where a proxy routes a request to one backend but the backend interprets it as destined for another host. This discrepancy enables request-smuggling style attacks, cache poisoning, or bypassing host-based access controls when an attacker supplies duplicate Host headers.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":45.1,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}