CVE-2021-42664

lowpriority · track · 33EPSS 0.017 · 77 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

1.67% (77th) EPSS

CVSS 3.5 · low

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

A Stored Cross Site Scripting (XSS) Vulneraibiilty exists in Sourcecodester Engineers Online Portal in PHP via the (1) Quiz title and (2) quiz description parameters to add_quiz.php. An attacker can leverage this vulnerability in order to run javascript commands on the web server surfers behalf, which can lead to cookie stealing and more.

cvss

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

5.4

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.5–5.4

v2.03.5lowAV:N/AC:M/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 6.8 · impact 2.9

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.3 · impact 2.7

v3.15.1mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

exploits (1)

Public proof-of-concept and weaponised exploit code.

0xDeku/CVE-2021-42664 CVE-2021-42664 - Stored Cross-Site Scripting vulnerability in the Engineers online portal system.PoC · poc_in_github

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
engineers online portal project engineers online portal= 1.0nvdUScpe:2.3:a:engineers_online_portal_project:engineers_online_portal:*:*:*:*:*:*:*:*

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 2021-11-05modified 2026-06-17

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+53084 more

references (13)

External citations — patches, advisories, analysis.

scry

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