CVE-2026-91145

Activiti through 7.1.0.M6 fails to validate hash-brace deferred expressions in process variables, allowing attackers to bypass expression filtering. Attackers can inject expressions beginning with #{ that are stored and later evaluated in the full Spring context when a mail task uses variable-backed body fields, enabling method invocation on application beans.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/Activiti/Activiti
https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-api-impl/activiti-api-process-runtime-impl/src/main/java/org/activiti/runtime/api/impl/ExpressionResolver.java
https://github.com/Activiti/Activiti/blob/7.1.0.M6/activiti-core/activiti-engine/src/main/java/org/activiti/engine/impl/bpmn/behavior/MailActivityBehavior.java
https://github.com/Activiti/Activiti/issues/5438
https://www.vulncheck.com/advisories/activiti-through-7.1.0-m6-expression-injection-via-mail-task
https://github.com/Activiti/Activiti/issues/5438

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-14 22:16

Updated : 2026-09-15 14:17

NVD link : CVE-2026-91145

Mitre link : CVE-2026-91145

CVE.ORG link : CVE-2026-91145

JSON object : View

Products Affected

No product.

CWE

CWE-917

Improper Neutralization of Special Elements used in an Expression Language Statement ('Expression Language Injection')

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