CVE-2026-3967 Alfresco Activiti Process Variable Serialization System SerializableType.java createObjectInputStream deserialization
Remote attackers can execute arbitrary code via unsafe deserialization in the Activiti process variable serialization system.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-3967?
CVE-2026-3967 is a medium-severity unsafe deserialization vulnerability in Alfresco Activiti, published on 12 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw has been found in Alfresco Activiti up to 7.19/8.8.0. Affected by this issue is the function deserialize/createObjectInputStream of the file activiti-core/activiti-engine/src/main/java/org/activiti/engine/impl/variable/SerializableType.java of the component Process Variable Serialization System. This manipulation causes deserialization. Remote exploitation of the attack is possible. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Which versions are affected by CVE-2026-3967?
How do I fix CVE-2026-3967?
No fix has been published for CVE-2026-3967 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-3967 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3967 exists.
Sources
Also known as GHSA-7wmq-q36p-g2wg.