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Fencer Intel
medium 6.1

CVE-2026-120638 json

CGI versions before 5.00 for Perl allow open redirects via HTML entity decoding of the URL after application validation in redirect

published 6d ago modified 7h ago also EUVD-2026-116605

cvss
6.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits
0
none known

Summary

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.

Patch / fix

  • cpan CGI 5.00
  • perl-CGI openSUSE Tumbleweed 5.20.0-1.1

opensuse advisories openSUSE-SU-2026:12465-1

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-120638 updated cvss 6.1

perl-cgi: perl-cgi: Open redirect via HTML entity decoding in redirect function

  • Red Hat Enterprise Linux 7 perl-CGI 4.61-5.el10 Red Hat Enterprise Linux 8 perl-CGI 4.61-5.el10 Red Hat Enterprise Linux 9 perl-CGI 4.61-5.el10 Red Hat Enterprise Linux 10 perl-CGI 4.61-5.el10
    affected: no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
7h ago

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CISA ADP 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

  • cpan CGI

Classification

Weakness
  • CWE-180 Incorrect Behavior Order: Validate Before Canonicalize
  • CWE-601 URL Redirection to Untrusted Site

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.