[ CVE-2026-55836 · Published 16 Oct 2026 ]
Vulnerability in open-zaak
[ Why it matters ]Priority signals
- Public proof-of-concept exploit exists (CISA SSVC)
[ Description ]Official description
Open Zaak is an open-source data and services layer for Dutch case-oriented working. From 1.13.0 until 1.27.2, 1.28.2, and 1.29.0, _import_document_row in src/openzaak/components/documenten/tasks.py uses the attacker-controlled bestandspad CSV field without ensuring that the resolved path remains under IMPORT_DOCUMENTEN_BASE_DIR. A client with an all-authorizations application token can supply an absolute or parent-traversal path to a file readable by the Celery service account. The worker copies that file into document storage, allowing its contents to be retrieved through the normal document download API and exposing server secrets or other private files. This issue is fixed in versions 1.27.2, 1.28.2, and 1.29.0.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.
[ References ]References
- github.com/open-zaak/open-zaak/commit/4b23957b55ab792bc2ba1fbc5ce6918881b62ab8
- github.com/open-zaak/open-zaak/commit/69c78ce2a0edb45bec8809bc2205585c5f8a4054
- github.com/open-zaak/open-zaak/commit/8acd5e59e0132aa19284bf22f7b3defca279e2ce
- github.com/open-zaak/open-zaak/releases/tag/1.27.2
- github.com/open-zaak/open-zaak/releases/tag/1.28.2
- github.com/open-zaak/open-zaak/releases/tag/1.29.0
- github.com/open-zaak/open-zaak/security/advisories/GHSA-x5cj-23hr-5r54