CVE-2021-34823
The ON24 ScreenShare (aka DesktopScreenShare.app) plugin before 2.0 for macOS allows remote file access via its built-in HTTP server.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.98%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- EPSS
- 1.98% probability · 79th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-611
- Affected
- on24/screenshare
- Source
- cve@mitre.org
References
- 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=29105Third Party Advisory
- 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=29105Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.