# CVE-2026-120631: CGI::Cookie versions from 4.67 before 5.00 for Perl allow denial of service via the client cookie expires value used as a regex in parse

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

CGI::Cookie versions from 4.67 before 5.00 for Perl allow denial of service via the client cookie expires value used as a regex in parse.

CGI's cookie method reads the Cookie request header through parse, which interpolates the header's expires value unescaped into the substitution pattern that removes it from the cookie string.

A client can make the request die with an invalid pattern, or tie up the process with one that backtracks catastrophically.

## 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/95e044af2ec24d99a61e99d6291580ad47aff641.patch

## Affected products and versions

-  /  (CGI): ≥ 4.67; < 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-1333, CWE-625

## 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/Cookie.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/95e044af2ec24d99a61e99d6291580ad47aff641.patch (CNA: CPANSec; patch)

## Provenance

- CNA: CPANSec: https://www.cve.org/CVERecord?id=CVE-2026-120631; retrieved 2026-11-04; source updated 2026-11-03

Revision: 2337368f7991ebd15903a4d08508cdca69a1212b1c80a39dd8a9e9b96824de86

Canonical: https://y2.dev/cve/CVE-2026-120631

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.