Quick answers
- Is CVE-2026-120646 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-120646 being exploited in the wild.
- How severe is CVE-2026-120646?
- Informational severity, published 4 November 2026.
- Which products and versions are affected?
- Perl CGI.pm 4.71 before 5.00.
- Is there a fix for CVE-2026-120646?
- Yes: fixed in CGI.pm 5.00 and later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-120646 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-120646?
- Check whether you run Perl CGI.pm at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: CGI.pm 5.00 and later
Technical details
The uploadInfo() method in CGI.pm dereferences its argument without type checking, treating plain strings as symbolic references. When a parameter value matches a defined global variable name (e.g., "0" for $0, or "VERSION"), the code attempts to call a method on the string, causing an exception. A remote attacker can exploit this via query parameters to trigger application crashes. The fix checks that the argument is a reference with a filename method before proceeding.
Affected products
- Perl CGI.pm 4.71 before 5.00
Timeline
- 2026-11-04: disclosed
- 2026-11-02: patched: Fix committed to GitHub