CVE-2026-120635

What it is

CGI versions before 5.00 for Perl allow form fields to be smuggled past proxies and WAFs via multipart parsing that differs from the RFCs. The multipart/form-data parser matches the boundary anywhere rather than at the start of a line, uses the boundary without its leading -- for some client-supplied User-Agent values, finds the Content-Disposition name and filename inside the quoted values of other parameters, and corrupts parts when the boundary nears the 4096-byte read size.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data exposure, service disruption.

Exploit odds

0.2% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-11-02 17:40 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-11-04 00:17 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-11-09 19:16 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.2% in the next 30 days (EPSS).
• Severity: 8.1 HIGH (CVSS).
• Fix: a patch or advisory is linked.

Details

Published

2026-11-04 00:17 UTC

Last modified

2026-11-09 19:16 UTC

Exploit probability

0.2% · EPSS, next 30 days

Weakness

CWE-436

Record status

Deferred

Attack profile CVSS 3.1 · 8.1

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-120635.md and follow it. Check whether this project is affected by CVE-2026-120635. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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