CVE-2021-43817

Reflected Cross-Site-Scripting vulnerability in Collabora Online

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.

Category

8.2
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.21%
Third-Party Advisory github.com
Affected: CollaboraOnline online
Published at:
Updated at:

References

Link Tags
https://github.com/CollaboraOnline/online/security/advisories/GHSA-7f6h-v9mx-58q9 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-43817?
CVE-2021-43817 has been scored as a high severity vulnerability.
How to fix CVE-2021-43817?
To fix CVE-2021-43817, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-43817 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43817 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43817?
CVE-2021-43817 affects CollaboraOnline online.
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