CVE-2021-34823

Description

The ON24 ScreenShare (aka DesktopScreenShare.app) plugin before 2.0 for macOS allows remote file access via its built-in HTTP server. This allows unauthenticated remote users to retrieve files accessible to the logged-on macOS user. When a remote user sends a crafted HTTP request to the server, it triggers a code path that will download a configuration file from a specified remote machine over HTTP. There is an XXE flaw in processing of this configuration file that allows reading local (to macOS) files and uploading them to remote machines.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.90% Top 20%
Third-Party Advisory trustwave.com Third-Party Advisory trustwave.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/ third party advisory
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=29105 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34823?
CVE-2021-34823 has been scored as a critical severity vulnerability.
How to fix CVE-2021-34823?
To fix CVE-2021-34823, 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-2021-34823 being actively exploited in the wild?
It is possible that CVE-2021-34823 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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