CVE-2023-35927

Summary

NextCloud Server and NextCloud Enterprise Server provide file storage for Nextcloud, a self-hosted productivity platform. In NextCloud Server versions 25.0.0 until 25.0.7 and 26.0.0 until 26.0.2 and Nextcloud Enterprise Server versions 21.0.0 until 21.0.9.12, 22.0.0 until 22.2.10.12, 23.0.0 until 23.0.12.7, 24.0.0 until 24.0.12.2, 25.0.0 until 25.0.7, and 26.0.0 until 26.0.2, when two server are registered as trusted servers for each other and successfully exchanged the share secrets, the malicious server could modify or delete VCards in the system addressbook on the origin server. This would impact the available and shown information in certain places, such as the user search and avatar menu. If a manipulated user modifies their own data in the personal settings the entry is fixed again.

Nextcloud Server n 25.0.7 and 26.0.2 and Nextcloud Enterprise Server 21.0.9.12, 22.2.10.12, 23.0.12.7, 24.0.12.2, 25.0.7, and 26.0.2 contain a patch for this issue. A workaround is available. Remove all trusted servers in the "Administration" > "Sharing" settings …/index.php/settings/admin/sharing. Afterwards, trigger a recreation of the local system addressbook with the following occ dav:sync-system-addressbook.

Affected Software

VendorProductVersion RangeStatus
nextcloudsecurity-advisoriesNextcloud Server >= 25.0.0, < 25.0.7affected
nextcloudsecurity-advisoriesNextcloud Server >= 26.0.0, < 26.0.2affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 25.0.0, < 25.0.7affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 26.0.0, < 26.0.2affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 21.0.0, < 21.0.9.12affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 22.0.0, < 22.2.10.12affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 23.0.0, < 23.0.12.7affected
nextcloudsecurity-advisoriesNextcloud Enterprise Server >= 24.0.0, < 24.0.12.2affected

Weaknesses

  • CWE-284: CWE-284: Improper Access Control

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References