Is CVE-2021-42342 actively exploited?

No active exploitation of CVE-2021-42342 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-42342 be exploited remotely?

Yes. CVE-2021-42342 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-42342?

CVE-2021-42342 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2021-42342

CRITICAL

CVE-2021-42342

CWE-434Published: October 14, 2021· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

An issue was discovered in GoAhead 4.x and 5.x before 5.1.5. In the file upload filter, user form variables can be passed to CGI scripts without being prefixed with the CGI prefix. This permits tunneling untrusted environment variables into vulnerable CGI scripts.

NVD Source

Technical Analysis

CVE-2021-42342 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.