CVE-2021-39183

Public Exploit
Unsafe inline XSS Owncast

Description

Owncast is an open source, self-hosted live video streaming and chat server. In affected versions inline scripts are executed when Javascript is parsed via a paste action. This issue is patched in 0.0.9 by blocking unsafe-inline Content Security Policy and specifying the script-src. The worker-src is required to be set to blob for the video player.

Category

8.2
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.33%
Third-Party Advisory github.com
Affected: owncast owncast
Published at:
Updated at:

References

Link Tags
https://github.com/owncast/owncast/security/advisories/GHSA-2hfj-cxw7-g45p third party advisory patch exploit

Frequently Asked Questions

What is the severity of CVE-2021-39183?
CVE-2021-39183 has been scored as a high severity vulnerability.
How to fix CVE-2021-39183?
To fix CVE-2021-39183, 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-2021-39183 being actively exploited in the wild?
It is possible that CVE-2021-39183 is being exploited or will be exploited in a near future based on public information. 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-2021-39183?
CVE-2021-39183 affects owncast owncast.
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