CVE-2026-56725 (GCVE-0-2026-56725)
Vulnerability from cvelistv5 – Published: 2026-09-25 17:09 – Updated: 2026-09-29 19:37
VLAI
EPSS
VEX
Title
Zammad: Denial of Service via OTRS Import Controller
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 19:37 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/zammad/zammad/security/advisor… | x_refsource_CONFIRM |
| https://github.com/zammad/zammad/commit/a04a95b69… | x_refsource_MISC |
| https://github.com/zammad/zammad/releases/tag/7.0.2 | x_refsource_MISC |
Impacted products
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"lastModified": "2026-09-29T20:17:20.750",
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"modifiedSubAvailabilityImpact": "NOT_DEFINED",
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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