CVE-2023-6877: RSS Aggregator by Feedzy – Feed to Post, Autoblogging, News & YouTube Video Feeds Aggregator <= 4.3.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Error Message

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-07 · updated 2026-06-17
Weakness: CWE-79

Description

The RSS Aggregator by Feedzy – Feed to Post, Autoblogging, News & YouTube Video Feeds Aggregator plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's shortcode(s) in all versions up to, and including, 4.3.3 due to insufficient input sanitization and output escaping on the Content-Type field of error messages when retrieving an invalid RSS feed. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Affected products

themeisle RSS Aggregator by Feedzy – Feed to Post, Autoblogging, News & YouTube Video Feeds Aggregator: before 4.3.4 — fixed in 4.3.4

How to fix

Upgrade to a fixed version: themeisle RSS Aggregator by Feedzy – Feed to Post, Autoblogging, News & YouTube Video Feeds Aggregator 4.3.4. Check the vendor advisory for mitigations.

References

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