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Public proof of concept

CVE-2021-39409

A public proof of concept exists; no exploitation attested.

  • Published2022-06-24

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability exists in Online Student Rate System v1.0 that allows any user to register as an administrator without needing to be authenticated.

Timeline

dates in UTC
  1. 2022-06-2417:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-04 09:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-39409?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-39409?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Online student rate system project online student rate system
BranchAffectedFixed in
1.0= 1.0no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

No fix published by the sources we read yet. NVD record

Detection

read 2026-11-03 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
1 repository, unverifiedStefanDorresteijn/CVE-2021-39409
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2022-06-24
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-39409?

A vulnerability exists in Online Student Rate System v1.0 that allows any user to register as an administrator without needing to be authenticated.

Is CVE-2021-39409 actively exploited?

Active exploitation of CVE-2021-39409 has not been confirmed. Its EPSS score was 2.8% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-39409?

CVE-2021-39409 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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Sources for this record