CVE-2026-120639 json
CGI versions before 5.00 for Perl allow HTTP header injection via entity decoding after the newline check in header and unchecked values in multipart_start and do_push
published 2026-11-03 5 d ago modified 2026-11-04 4 d ago also EUVD-2026-116606
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 13%
- public exploits
- 0
- none known
Summary
CGI versions before 5.00 for Perl allow HTTP header injection via entity decoding after the newline check in header and unchecked values in multipart_start and do_push.
With autoEscape off, header decodes HTML entities in extra header values after its newline check, so an encoded CR or LF reaches the response. multipart_start does not check header values for newlines, and do_push does not check the type it prints in each part.
An application that passes request data into these header values can be made to add headers or split the response.
Patch / fix
- perl-CGI openSUSE Tumbleweed 5.20.0-1.1
opensuse advisories openSUSE-SU-2026:12465-1
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-2026-120639 updated cvss 6.5
perl-cgi: perl-cgi: HTTP header injection via improper newline validation
-
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.el10affected: 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
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).
Classification
- Weakness
-
- CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers
References
-
github.com
/leejo/CGI.pm/commit/69955309d371c8093d11cf12e3ddef491537ffad.patch
patch
-
github.com
/leejo/CGI.pm/commit/7733c2753f4f240012097507cda2b6e87ae46db4.patch
patch
-
metacpan.org
/release/LEEJO/CGI-4.72/source/lib/CGI.pm
technical-description
-
metacpan.org
/release/LEEJO/CGI-5.00/changes
release-notes
Sources
- CVE List CVE-2026-120639
- NVD CVE-2026-120639
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