Vulnerability · Published Nov 3, 2026 · Assigned by CPANSec
CVE-2026-120638CGI versions before 5.00 for Perl allow open redirects via HTML entity decoding of the URL after application validation in redirect
Unrated
In plain English
A open redirect in CGI. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).
Severity (CVSS )–Not rated
Exploit odds (30 days)0.2%top 92.3% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
CGI versions before 5.00 for Perl allow open redirects via HTML entity decoding of the URL after application validation in redirect. redirect decodes HTML entities in its URL before writing the Location header, so a URL the application has already validated can change meaning. For example, //evil.example/ becomes //evil.example/ and sends the user to another host.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | libcgi-pm-perl | no fix listed | DEBIAN-CVE-2026-120638 |
| Debian:13 | libcgi-pm-perl | no fix listed | DEBIAN-CVE-2026-120638 |
| Debian:14 | libcgi-pm-perl | no fix listed | DEBIAN-CVE-2026-120638 |
| Ubuntu:22.04:LTS | libcgi-pm-perl | no fix listed | UBUNTU-CVE-2026-120638 |
| Ubuntu:24.04:LTS | libcgi-pm-perl | no fix listed | UBUNTU-CVE-2026-120638 |
| Ubuntu:26.04:LTS | libcgi-pm-perl | no fix listed | UBUNTU-CVE-2026-120638 |
| Ubuntu:26.10 | libcgi-pm-perl | no fix listed | UBUNTU-CVE-2026-120638 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| CGI | 0 – before 5.00 |
Weakness: CWE-180, CWE-601