CVE-2026-27727

CVE-2026-27727 is a critical-severity vulnerability in Mchange Mchange Commons Java with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-74.

Key facts

Description

mchange-commons-java, a library that provides Java utilities, includes code that mirrors early implementations of JNDI functionality, including support for remote `factoryClassLocation` values, by which code can be downloaded and invoked within a running application. If an attacker can provoke an application to read a maliciously crafted `jaxax.naming.Reference` or serialized object, they can provoke the download and execution of malicious code. Implementations of this functionality within the JDK were disabled by default behind a System property that defaults to `false`, `com.sun.jndi.ldap.object.trustURLCodebase`. However, since mchange-commons-java includes an independent implementation of JNDI derefencing, libraries (such as c3p0) that resolve references via that implementation could be provoked to download and execute malicious code even after the JDK was hardened. Mirroring the JDK patch, mchange-commons-java's JNDI functionality is gated by configuration parameters that default to restrictive values starting in version 0.4.0. No known workarounds are available. Versions prior to 0.4.0 should be avoided on application CLASSPATHs.

Frequently asked questions

What is CVE-2026-27727?
mchange-commons-java, a library that provides Java utilities, includes code that mirrors early implementations of JNDI functionality, including support for remote `factoryClassLocation` values, by which code can be downloaded and invoked within a running application. If an attacker can provoke an application to read a maliciously crafted `jaxax.naming.Reference` or serialized object, they can provoke the download and execution of malicious code. Implementations of this functionality within the JDK were disabled by default behind a System property that defaults to `false`, `com.sun.jndi.ldap.object.trustURLCodebase`. However, since mchange-commons-java includes an independent implementation of JNDI derefencing, libraries (such as c3p0) that resolve references via that implementation could be provoked to download and execute malicious code even after the JDK was hardened. Mirroring the JDK patch, mchange-commons-java's JNDI functionality is gated by configuration parameters that default to restrictive values starting in version 0.4.0. No known workarounds are available. Versions prior to 0.4.0 should be avoided on application CLASSPATHs.
How severe is CVE-2026-27727?
CVE-2026-27727 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-27727 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27727?
CVE-2026-27727 affects Mchange Mchange Commons Java. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27727?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2026-27727 have an EU (EUVD) identifier?
Yes. CVE-2026-27727 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-8683.
When was CVE-2026-27727 published?
CVE-2026-27727 was published on 2026-02-25 and last updated on 2026-07-02.

References

Affected products (1)

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