CVE-2021-42342

Q: How do I fix CVE-2021-42342?

Upgrade goahead to 5.1.5 or later.

Q: Is CVE-2021-42342 being actively exploited?

Not that we know of. CVE-2021-42342 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 59.5% is the estimated probability that it will be exploited in the next 30 days. That is higher than 99% of all scored CVEs.

Q: How severe is CVE-2021-42342?

CVE-2021-42342 has a CVSS v3 base score of 9.8, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

Q: What does CVE-2021-42342 affect?

Published advisories record a fix for goahead (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

CRITICALEPSS 99th pctl

9.8

CVSS v3

NVD

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.

CWE-434Unrestricted File Upload

How to fix

Remediation Available

goaheadNVD

Affected:>= 5.0.0, < 5.1.5Fixed in:5.1.5CVE-2021-42342derived from NVD

TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploit Intelligence

59.46%probability of exploitation in 30 days

99thpercentile

Very high risk: more likely to be exploited than 99% of all known CVEs.

References

Third-Party Advisory1

github.com

Related Vulnerabilities

Other CWE-434 (Unrestricted File Upload) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2017-12617	High	8.1	100%	KEV	Fix
CVE-2018-15961	Critical	9.8	100%	KEV	-
CVE-2021-31207	Medium	6.6	100%	KEV + Ransom	Fix
CVE-2017-12615	High	8.1	100%	KEV + Ransom	-
CVE-2025-31324	Critical	10.0	100%	KEV + Ransom	-
CVE-2024-50623	Critical	9.8	99%	KEV + Ransom	Fix

Common questions

How do I fix CVE-2021-42342?

Upgrade goahead to 5.1.5 or later.

Is CVE-2021-42342 being actively exploited?

Not that we know of. CVE-2021-42342 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 59.5% is the estimated probability that it will be exploited in the next 30 days. That is higher than 99% of all scored CVEs.

How severe is CVE-2021-42342?

CVE-2021-42342 has a CVSS v3 base score of 9.8, rated critical. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.

What does CVE-2021-42342 affect?

Published advisories record a fix for goahead (NVD). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.

Embed a live status badge for CVE-2021-42342

Markdown

[![CVE-2021-42342](https://tridentstack.com/cve/badge/CVE-2021-42342.svg)](https://tridentstack.com/cve/CVE-2021-42342)

HTML

<a href="https://tridentstack.com/cve/CVE-2021-42342"><img src="https://tridentstack.com/cve/badge/CVE-2021-42342.svg" alt="CVE-2021-42342"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

See how it works Start freeThis CVE lookup is free and always will be.

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.