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Case File

CVE-2021-43817

HIGH · CVSS 8.2 EPSS 0.65% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-12-13 · Last synced 2026-08-04

CyberRota Analysis

This is a high severity vulnerability with a CVSS score of 8.2. It affects Office. Public exploit code or proof-of-concept references have been detected in its references.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

GitHub PoC Links

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-43817
Severity
HIGH
CVSS
8.2
EPSS
0.65%
Office

Original NVD Description

Collabora Online is a collaborative online office suite based on LibreOffice technology. In affected versions a reflected XSS vulnerability was found in Collabora Online. An attacker could inject unescaped HTML into a variable as they created the Collabora Online iframe, and execute scripts inside the context of the Collabora Online iframe. This would give access to a small set of user settings stored in the browser, as well as the session's authentication token which was also passed in at iframe creation time. Users should upgrade to Collabora Online 6.4.16 or higher or Collabora Online 4.2.20 or higher. Collabora Online Development Edition 21.11 is not affected.

Related CVEs

Other vulnerabilities affecting the same vendor(s)