Files
ilnmors-homelab/docs/issues/crowdsec/260502_nextcloud.md
T
il 880857a70a fix(crowdsec): update parser 'crowdsecurity/nextcloud-whitelist'
update note:
- deprecate custom whitelist expression
- apply 'crowdsecurity/nextcloud-whitelist' parser
2026-05-03 07:19:59 +09:00

1.4 KiB

Nextcloud crowdsec false positive issue

Status

  • Finished

Date

  • 2026-05-02

Version

  • Nextcloud: 33.0.3

Problem

  • When users download or modify some files, all connections to homelab services are refused.
    • fw ban users' IP address.

Reason

  • Nextcloud has a lot of workflows which can be caught from crowdsec

Timeline

  • 2026-05-02: Release nextcloud
  • 2026-05-02: Find the false positive case, and add whitelist
  • 2026-05-03: Install crowdsecurity/nextcloud-whitelist parser
  • 2026-05-03: Make previous expressions annotation

Solution

  • Install crowdsecurity/nextcloud-whitelist on auth node

Deprecated solution

  • Access to fw
    • Check the ban list with sudo cscli alerts list
    • Read the ban case with sudo cscli alerts inspect $NUMBER
  • Add expressions on whitelist
    • evt.Meta.target_fqdn == '{{ services['nextcloud']['domain']['public'] }}.{{ domain['public'] }}' && evt.Meta.http_path contains '/apps/viewer/js/'
    • evt.Meta.target_fqdn == '{{ services['nextcloud']['domain']['public'] }}.{{ domain['public'] }}' && evt.Meta.http_path contains '/dist/'
    • evt.Meta.target_fqdn == '{{ services['nextcloud']['domain']['public'] }}.{{ domain['public'] }}' && evt.Meta.http_path contains '/remote.php/dav/files/'
  • Delete false positive decision
    • Check false positive decision with sudo cscli decision list
    • Delete false positive decision with sudo cscli decision delete --id $ID