{"affected":[{"defaultStatus":"unaffected","ecosystem":"cpan","packageName":"CGI","product":"","source":"CNA: CPANSec","vendor":"","versions":[{"lessThan":"5.00","status":"affected","version":"0","versionType":"custom"}]}],"cveId":"CVE-2026-120633","cwes":["CWE-348","CWE-601"],"description":"CGI versions before 5.00 for Perl trust the client X-Forwarded-Host header in url, self_url, virtual_host and virtual_port.\n\nThese take the host name and port from the X-Forwarded-Host request header when present, and otherwise from Host, without validating either. The URLs from url and self_url are the default redirect location and the start_html(-base=>1) base href, and the default start_form action when REQUEST_URI is not set.\n\nA client can poison shared caches, and URLs the application stores or sends, with redirects, links and scripts that point at a host it controls.","epss":null,"exploits":[],"kev":null,"metrics":[],"modifiedAt":1793749204604,"publishedAt":1793749204604,"references":[{"source":"CNA: CPANSec","tags":["technical-description"],"url":"https://metacpan.org/release/LEEJO/CGI-4.72/source/lib/CGI.pm"},{"source":"CNA: CPANSec","tags":["release-notes"],"url":"https://metacpan.org/release/LEEJO/CGI-5.00/changes"},{"source":"CNA: CPANSec","tags":["patch"],"url":"https://github.com/leejo/CGI.pm/commit/d76752a5e8dfd365b0fe3a0b9a7da6c054e856af.patch"}],"remediation":[{"kind":"fix","source":"CNA: CPANSec","text":"Upgrade to CGI 5.00 or later."},{"kind":"workaround","source":"CNA: CPANSec","text":"For deployments that cannot upgrade, strip X-Forwarded-Host at the web server or proxy unless it sets the header itself, and validate Host."},{"kind":"fix","source":"CNA: CPANSec","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/leejo/CGI.pm/commit/d76752a5e8dfd365b0fe3a0b9a7da6c054e856af.patch"}],"revision":"ca49ea8df1b9ba18fb6d9b82fdd9725b9d96ae32b08d92b5195f2e14c533671e","sources":[{"modifiedAt":1793749204604,"name":"CNA: CPANSec","retrievedAt":1793750970812,"url":"https://www.cve.org/CVERecord?id=CVE-2026-120633"}],"ssvc":null,"status":"published","title":"CGI versions before 5.00 for Perl trust the client X-Forwarded-Host header in url, self_url, virtual_host and virtual_port","updatedAt":1793750970812}