CVE-2026-27727: mchange-commons-java: Remote Code Execution via JNDI Reference Resolution
CVE-2026-27727 affects mchange-commons-java before 0.4.0, where an independent JNDI implementation can be induced to download and run remote code when it processes a crafted reference or serialized object. NVD assigns a CVSS base score of 9.8, and the vendor advisory states that JNDI functionality is gated by restrictive defaults starting in 0.4.0. No confirmed active exploitation appears in the sources consulted, and the CVE is not listed in CISA KEV.
Overview
The vendor advisory describes a remote code execution issue in mchange-commons-java, a Java utilities library. Its independent JNDI handling can be induced to download and run code from a remote location when it resolves a crafted reference or serialized object. The advisory notes that libraries such as c3p0 that rely on this path were exposed even after the JDK hardened its own JNDI behavior. See the vendor advisory.
Impact
- The CVSS vector rates confidentiality, integrity and availability impact as high, and NVD assigns a base score of 9.8.
- Successful exploitation would allow code from a remote location to run inside the affected application.
- Applications that depend on mchange-commons-java before 0.4.0, especially those using c3p0, are the main concern.
Affected products and versions
- Mchange Mchange Commons Java: before 0.4.0.
- Swaldman Mchange-commons-java: before 0.4.0.
- The record identifies 0.4.0 as the first version whose JNDI functionality defaults to restrictive values.
Exploitation status
CISA KEV does not list this CVE, and no confirmed active exploitation appears in the sources consulted. The SSVC data in the record indicates a proof-of-concept exploitation status and marks automatability as no. A proof-of-concept status is an assessment and does not confirm attacks in the wild.
Remediation and mitigation
- Upgrade mchange-commons-java to 0.4.0 or later.
- Review dependency trees for direct and transitive use, including c3p0 and other libraries that resolve references.
- The record states that no known workarounds are available, so upgrading is the primary control.
- The advisory states that versions before 0.4.0 should be avoided on application CLASSPATHs.
Detection guidance
- Inventory application and container dependencies to identify mchange-commons-java artifacts and their versions.
- Monitor for unexpected outbound connections from application servers to remote hosts, and for unexpected class loading, as high-level signals.
- Review application logs for naming-lookup or deserialization errors that originate from components using the library.
Limitations of the available information
- The record does not describe the exact vulnerable code paths or the full set of configurations that are affected.
- Several Red Hat errata are listed in the references, but their content is not part of the record, so product-specific fix status is unknown.
- This analysis does not reproduce exploit code, and the record does not confirm real-world attacks.
Frequently asked questions
Which versions of mchange-commons-java are affected by CVE-2026-27727?
The record lists versions before 0.4.0 as affected. Version 0.4.0 is the first version in the record whose JNDI functionality defaults to restrictive values.
Is CVE-2026-27727 being actively exploited?
The CVE is not listed in CISA KEV, and no confirmed active exploitation appears in the sources consulted. The SSVC data indicates a proof-of-concept status, which is an assessment and not confirmation of attacks.
This analysis was drafted with AI assistance from verified source data and automatically checked against it.