Zammad: Denial of Service via OTRS Import Controller
Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.2, summary An unauthenticated request to POST /api/v1/import/otrs/import_check blocks a Zammad request worker for roughly two minutes. The import_check and import_status actions are missing the setup_done_response guard that other actions in the same controller carry, so they execute on fully set-up production instances. The action enters a retry loop against a blank OTRS endpoint, sleeping for 30 s + 45 s between attempts. Impact An unauthenticated remote attacker denies service to a production Zammad instance. Each request costs almost nothing and forces ~115 seconds of server-side blocking. A few requests per second saturate the Puma worker pool. The condition persists as long as the traffic continues. No account, valid import configuration, or target knowledge beyond the hostname is needed. CSRF token is trivially obtained from any prior GET response. This issue is fixed in version 7.0.2.
Evidence and details
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-56725
zammad
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
- Related CVEs
- CVE-2026-56725
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics