# CVE-2026-120647: CGI versions before 5.00 for Perl allow Content-Disposition parameter injection via unescaped double quotes in the header attachment filename

Status: published. Published: 2026-11-03. Updated: 2026-11-03.

CGI versions before 5.00 for Perl allow Content-Disposition parameter injection via unescaped double quotes in the header attachment filename.

header(-attachment => $name) writes $name into the quoted filename parameter of Content-Disposition without escaping double quotes.

An application that passes request data as the attachment name can be made to send a second filename parameter, changing the name the response is saved under.

## Remediation

- fix: Upgrade to CGI 5.00 or later. (source: CNA: CPANSec)
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: CPANSec) — https://github.com/leejo/CGI.pm/commit/131280a5c5bc51b65797bd57ef0ee8da8468065b.patch

## Affected products and versions

-  /  (CGI): ≥ 0; < 5.00 (affected, custom). Source: CNA: CPANSec

## Severity and prioritization

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-116

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://metacpan.org/release/LEEJO/CGI-4.72/source/lib/CGI.pm (CNA: CPANSec; technical-description)

- https://metacpan.org/release/LEEJO/CGI-5.00/changes (CNA: CPANSec; release-notes)

- https://github.com/leejo/CGI.pm/commit/131280a5c5bc51b65797bd57ef0ee8da8468065b.patch (CNA: CPANSec; patch)

## Provenance

- CNA: CPANSec: https://www.cve.org/CVERecord?id=CVE-2026-120647; retrieved 2026-11-04; source updated 2026-11-03

Revision: 478e4161f8df0071402f134315f8408a392994c04b37acac1db4d2f1bae0a81f

Canonical: https://y2.dev/cve/CVE-2026-120647

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