CVE-2021-39250
CWE-79Published: August 17, 2021· Updated: Jun 17, 2026
Official Description
Invision Community (aka IPS Community Suite or IP-Board) before 4.6.5.1 allows stored XSS, with resultant code execution, because an uploaded file can be placed in an IFRAME element within user-generated content. For code execution, the attacker can rely on the ability of an admin to install widgets, disclosure of the admin session ID in a Referer header, and the ability of an admin to use the templating engine (e.g., Edit HTML).
Technical Analysis
CVE-2021-39250 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (4)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-39250 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts