CVE-2021-42342

highpriority · attend · 70EPSS 0.595 · 99 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

2 exploits · PoC

Likely / severe?

59.5% (99th) EPSS

CVSS 7.5 · high

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USprimary

exploits (2)

Public proof-of-concept and weaponised exploit code.

Mr-xn/CVE-2021-42342CVE-2021-42342 RCEPoC · poc_in_github
kimusan/goahead-webserver-pre-5.1.5-RCE-PoC-CVE-2021-42342-A small PoC for the recent RCE found in the Goahead Webserver prior to version 5.1.5. PoC · poc_in_github

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
embedthis goahead4.0.0 → 4.1.3nvdUScpe:2.3:a:embedthis:goahead:*:*:*:*:*:*:*:*
embedthis goahead5.0.0 → 5.1.5nvdUScpe:2.3:a:embedthis:goahead:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-10-14modified 2026-06-17

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references (4)

External citations — patches, advisories, analysis.

scry

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