CVE-2026-91197: Flowable flowable-engine through 8.0.0 XXE via ProcessDiagramLayoutFactory

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-14 · updated 2026-09-24
Weakness: CWE-611

Description

Flowable flowable-engine through 8.0.0 contains an XML external entity injection vulnerability in ProcessDiagramLayoutFactory.parseXml() that fails to disable external entity resolution when parsing deployed BPMN resources. Attackers with process deployment privileges can embed DOCTYPE declarations with external entities in BPMN files to read arbitrary local files or trigger requests to internal network endpoints when diagram layout is computed.

Affected products

flowable-engine: through 8.0.0

References

https://github.com/flowable/flowable-engine
https://github.com/flowable/flowable-engine/blob/0779d68e5a3385b74d8acb8bc37901ff54513249/modules/flowable-engine/src/main/java/org/flowable/engine/impl/bpmn/diagram/ProcessDiagramLayoutFactory.java#L101-L118
https://github.com/flowable/flowable-engine/blob/0779d68e5a3385b74d8acb8bc37901ff54513249/modules/flowable5-engine/src/main/java/org/activiti/engine/impl/bpmn/diagram/ProcessDiagramLayoutFactory.java#L97-L114
https://github.com/flowable/flowable-engine/issues/4216
https://www.vulncheck.com/advisories/flowable-flowable-engine-through-8.0.0-xxe-via-processdiagramlayoutfactory
https://github.com/flowable/flowable-engine/issues/4216

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