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Fencer Intel
medium 4.1

CVE-2021-36851 json

WordPress Testimonial Slider plugin <= 3.5.8.3 - Cross-Site Scripting (XSS) vulnerability

published 4y ago modified 4mo ago also EUVD-2021-23427

cvss
4.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 47%
public exploits
0
none known

Summary

Authenticated (editor or higher user role) Cross-Site Scripting (XSS) vulnerability in Web-Settler Testimonial Slider – Free Testimonials Slider Plugin (WordPress plugin) via parameters mpsp_posts_bg_color, mpsp_posts_description_color, mpsp_slide_nav_button_color.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 4.1 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:L/A:N
NVD 3.1 5.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 3.5 AV:N/AC:M/Au:S/C:N/I:P/A:N

Affected products

  • Web-Settler Testimonial Slider – Free Testimonials Slider Plugin (WordPress plugin)

Classification

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

References

Sources

Fencer Intel 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.