CVE-2021-24503: Popular Brand SVG Icons - Simple Icons < 2.7.8 - Contributor+ Stored XSS

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-02 · updated 2026-06-17
Weakness: CWE-79

Description

The Popular Brand Icons – Simple Icons WordPress plugin before 2.7.8 does not sanitise or validate some of its shortcode parameters, such as "color", "size" or "class", allowing users with a role as low as Contributor to set Cross-Site payload in them. A post made by a contributor would still have to be approved by an admin to have the XSS triggered in the frontend, however, higher privilege users, such as editor could exploit this without the need of approval, and even when the blog disallows the unfiltered_html capability.

Affected products

Popular Brand Icons – Simple Icons: before 2.7.8 — fixed in 2.7.8

How to fix

Upgrade to a fixed version: Popular Brand Icons – Simple Icons 2.7.8. Check the vendor advisory for mitigations.

References

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