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Public proof of concept

CVE-2021-39608

A public proof of concept exists; no exploitation attested.

  • Published2021-08-23
  • WeaknessCWE-434

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

Remote Code Execution (RCE) vulnerabilty exists in FlatCore-CMS 2.0.7 via the upload addon plugin, which could let a remote malicious user exeuct arbitrary php code.

Timeline

dates in UTC
  1. 2021-09-06Exploit-DB entryExploit-DB

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 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-2021-39608?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-39608?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Flatcore flatcore-cms
BranchAffectedFixed in
2.0= 2.0.7no 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 2026-11-02 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
EDB-50262
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • NVDCVSS 3.17.2read 2026-10-23
  • NVDCVSS 2.09read 2026-10-23
  • NVDweakness (CWE)CWE-434read 2026-10-23
  • FIRST EPSSEPSS score45.9 %read 2026-11-02
  • Exploit-DBdetectionread 2026-11-02

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Published
2021-08-23
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-39608?

Remote Code Execution (RCE) vulnerabilty exists in FlatCore-CMS 2.0.7 via the upload addon plugin, which could let a remote malicious user exeuct arbitrary php code.

Is CVE-2021-39608 actively exploited?

Active exploitation of CVE-2021-39608 has not been confirmed. Its EPSS score was 45.9% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-39608?

CVE-2021-39608 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

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Sources for this record