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Fencer Vulns
medium 6.4

CVE-2021-47919 json

Simple CMS 2.1 Non-Persistent Cross-Site Scripting via Preview Parameter

published 2026-02-01 9 mo ago modified 2026-06-17 4 mo ago also EUVD-2021-34752

cvss
6.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits
0
none known

Summary

Simple CMS 2.1 contains a non-persistent cross-site scripting vulnerability in the preview.php file's id parameter. Attackers can inject malicious script code through a GET request to execute arbitrary scripts and potentially hijack user sessions or perform phishing attacks.

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
9 mo ago

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • vulnerability-lab.com https://www.vulnerability-lab.com/get_content.php?id=2301 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
CNA 3.1 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
CNA 4.0 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected products

  • Simplephpscripts Simple CMS

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.