CVE-2022-41882
In version 3.6.0, if a user received a malicious file share and has it synced locally or the virtual filesystem enabled and clicked a nc://open/ link it will open the default editor for the file type of the shared file, which on Windows can also…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.49%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server with your computer. In version 3.6.0, if a user received a malicious file share and has it synced locally or the virtual filesystem enabled and clicked a nc://open/ link it will open the default editor for the file type of the shared file, which on Windows can also sometimes mean that a file depending on the type, e.g. "vbs", is being executed. It is recommended that the Nextcloud Desktop client is upgraded to version 3.6.1. As a workaround, users can block the Nextcloud Desktop client 3.6.0 by setting the `minimum.supported.desktop.version` system config to `3.6.1` on the server, so new files designed to use this attack vector are not downloaded anymore. Already existing files can still be used. Another workaround would be to enforce shares to be accepted by setting the `sharing.force_share_accept` system config to `true` on the server, so new files designed to use this attack vector are not downloaded anymore. Already existing shares can still be abused.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 0.49% probability · 41th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-94
- Affected
- nextcloud/desktop
- Source
- security-advisories@github.com
References
- https://github.com/nextcloud/desktop/pull/5039Patch, Third Party Advisory
- https://github.com/nextcloud/desktop/releases/tag/v3.6.1Release Notes, Third Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-3w86-rm38-8w63Third Party Advisory
- https://github.com/nextcloud/server/pull/34559Patch, Third Party Advisory
- https://github.com/nextcloud/desktop/pull/5039Patch, Third Party Advisory
- https://github.com/nextcloud/desktop/releases/tag/v3.6.1Release Notes, Third Party Advisory
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-3w86-rm38-8w63Third Party Advisory
- https://github.com/nextcloud/server/pull/34559Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.