CVE-2021-34823
CRITICALON24 ScreenShare < 2.0 - Unauthenticated XML External Entity Injection via HTTP Server
Title source: llmDescription
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.
References (2)
Core 2
Core References
Third Party Advisory x_refsource_misc
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/
Third Party Advisory x_refsource_misc
https://www.trustwave.com/en-us/resources/security-resources/security-advisories/?fid=29105
Scores
CVSS v3
9.1
EPSS
0.0198
EPSS Percentile
77.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Details
CWE
CWE-611
Status
published
Products (1)
on24/screenshare
< 2.0
Published
Aug 13, 2021
Tracked Since
Feb 18, 2026