CVE-2026-55153: mchange-commons-java is a Java library of shared utility classes used by mchange projects like the c3p0 connection pool.

mchange-commons-java is a Java library of shared utility classes used by mchange projects like the c3p0 connection pool.

mchange-commons-java is a Java library of shared utility classes used by mchange projects like the c3p0 connection pool. Prior to version 0.6.0, its JNDI ObjectFactory implementation (com.mchange.v2.naming.JavaBeanObjectFactory) will construct objects of arbitrary classes and initialize "JavaBean"-style properties, which for certain classes enables JNDI injection and "deserialization gadgets." Such initialization is unsafe for some classes: for example, setting the contentType property of a Swing JEditorPane to text/html and its text property to HTML containing a stylesheet <link> will provoke an HTTP GET on an arbitrary URL, potentially from within a trusted security domain. The problem is aggravated by the library's ReferenceIndirector, through which malicious JNDI Reference objects can be smuggled in for dereferencing wherever an application reads a Java-serialized object. This has been resolved in version 0.6.0.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses mchange-commons-java, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.19%, higher than 9% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

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Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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