CVE-2026-120633
Received
Received - Intake
CGI for Perl Host Header Injection Vulnerability
Vulnerability report for CVE-2026-120633, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-11-04
Last updated on: 2026-11-04
Assigner: CPANSec
Description
Description
CGI versions before 5.00 for Perl trust the client X-Forwarded-Host header in url, self_url, virtual_host and virtual_port.
These 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.
A client can poison shared caches, and URLs the application stores or sends, with redirects, links and scripts that point at a host it controls.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-601 | The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. |
| CWE-348 | The product has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack. |
