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Fencer Vulns
medium 6.1

CVE-2021-34640 json

Securimage-WP-Fixed <= 3.5.4 Reflected Cross-Site Scripting

published 2021-08-11 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21290

cvss
6.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
2.3%
EPSS 2.3% chance of exploitation in 30 days, percentile 83%
public exploits
0
none known, plus a Nuclei check

Summary

The Securimage-WP-Fixed WordPress plugin is vulnerable to Reflected Cross-Site Scripting due to the use of $_SERVER['PHP_SELF'] in the ~/securimage-wp.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 3.5.4.

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
17 mo ago

Exploit prediction

2.30% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • Nuclei template WordPress Securimage-WP-Fixed <=3.5.4 - Cross-Site Scripting nuclei detection template
  • plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/securimage-wp-fixed/trunk/securimage-wp.php#L628 referenced PoC, tagged "exploit" by a source, unverified
  • wordfence.com https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34640 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

  • Securimage-WP-Fixed Securimage-WP-Fixed

Classification

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

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.