CVE-2026-120631

HIGH
MEDIUM Priority: 0.04 BB Relevance: 75/100
Published: 2026-11-03 Modified: 2026-11-09 First seen: 2026-11-04 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: High

Description

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.

Affected Software (2)

VendorProductVersion
— — 4.67 < 5.00
— — 4.67 < 5.00

Bug Bounty Relevance

75 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.50%
Raw Score 0.004950
Percentile 43.0%
Date 2026-11-14

EPSS Trend

2026-11-14
0.00495
2026-11-13
0.00495
2026-11-12
0.00495
2026-11-10
0.00495
2026-11-09
0.00389
2026-11-08
0.00389
2026-11-07
0.00389
2026-11-06
0.00389
2026-11-05
0.00389
2026-11-04
0.00389

Intelligence Sources

mitre ref →
nvd ref →