{"id":"GHSA-5476-xc4j-rqcv","summary":"c3p0 vulnerable to Remote Code Execution via unsafe deserialization of userOverridesAsString property","details":"### Impact\n\nc3p0 is vulnerable to attack via maliciously crafted Java-serialized objects and `javax.naming.Reference` instances. Several c3p0 `ConnectionPoolDataSource` implementations have a property called `userOverridesAsString` which conceptually represents a `Map\u003cString,Map\u003cString,String\u003e\u003e`. Prior to v0.12.0, that property was maintained as a hex-encoded serialized object. Any attacker able to reset this property, on an existing `ConnectionPoolDataSource` or via maliciously crafted serialized objects or `javax.naming.Reference` instances could be tailored execute unexpected code on the application's `CLASSPATH`.\n\nThe danger of this vulnerability was strongly magnified by vulnerabilities in c3p0's main dependency, mchange-commons-java. This library includes code that mirrors early implementations of JNDI functionality, including ungated support for remote `factoryClassLocation` values. Attackers could set c3p0's `userOverridesAsString` hex-encoded serialized objects that include objects \"indirectly serialized\" via JNDI references. Deserialization of those objects and dereferencing of the embedded `javax.naming.Reference` objects could provoke download and execution of malicious code from a remote `factoryClassLocation`.\n\nAlthough hazard presented by c3p0's vulnerabilites are exarcerbated by vulnerabilities in mchange-commons-java, use of Java-serialized-object hex as the format for a writable Java-Bean property, of objects that may be exposed across JNDI interfaces, represents a serious independent fragility.\n\n### Patches\n\nThe `userOverridesAsString` property of c3p0 `ConnectionPoolDataSource` classes has been reimplemented to use a safe CSV-based format, rather than rely upon potentially dangerous Java object deserialization.\n\nc3p0-0.12.0+ and above depend upon mchange-commons-java 0.4.0+, which gates support for remote `factoryClassLocation` values by configuration parameters that default to restrictive values. Those parameters are documented [here](https://www.mchange.com/projects/c3p0/#configuring_security).\n\nc3p0 additionally enforces the new mchange-commons-java `com.mchange.v2.naming.nameGuardClassName` to prevent injection of unexpected, potentially remote JNDI names.\n\n### Workarounds\n\nUsers should upgrade to c3p0-0.12.0 or above. There is no supported workaround for earlier versions of c3p0.\n\n### References\n\n[c3p0, you little rascal — Hans-Martin Münch](https://mogwailabs.de/en/blog/2025/02/c3p0-you-little-rascal/)\n[c3p0 documentation, security note](https://www.mchange.com/projects/c3p0/#security-note)\n[c3p0 documentation, configuring security](https://www.mchange.com/projects/c3p0/#configuring_security)","aliases":["CVE-2026-27830"],"modified":"2026-07-17T21:11:53.000264612Z","published":"2026-02-25T18:35:23Z","database_specific":{"github_reviewed_at":"2026-02-25T18:35:23Z","nvd_published_at":"2026-02-26T01:16:24Z","cwe_ids":["CWE-502","CWE-94"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"WEB","url":"https://github.com/swaldman/c3p0/security/advisories/GHSA-5476-xc4j-rqcv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27830"},{"type":"WEB","url":"https://github.com/swaldman/c3p0/commit/e14cbd8166e423e2e9a9d6f08b2add3433492d6e"},{"type":"PACKAGE","url":"https://github.com/swaldman/c3p0"},{"type":"WEB","url":"https://mogwailabs.de/en/blog/2025/02/c3p0-you-little-rascal"},{"type":"WEB","url":"https://www.mchange.com/projects/c3p0/#configuring_security"},{"type":"WEB","url":"https://www.mchange.com/projects/c3p0/#security-note"}],"affected":[{"package":{"name":"com.mchange:c3p0","ecosystem":"Maven","purl":"pkg:maven/com.mchange/c3p0"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.12.0"}]}],"versions":["0.10.0","0.10.0-pre1","0.10.0-pre2","0.10.0-pre3","0.10.0-pre4","0.10.0-pre5","0.10.0-pre6","0.10.0-pre7","0.10.1","0.10.2","0.11.0","0.11.0-pre1","0.11.0-pre2","0.11.1","0.11.2","0.9.2","0.9.2-pre2-RELEASE","0.9.2-pre3","0.9.2-pre4","0.9.2-pre5","0.9.2-pre6","0.9.2-pre7","0.9.2-pre8","0.9.2.1","0.9.5","0.9.5-pre1","0.9.5-pre10","0.9.5-pre2","0.9.5-pre3","0.9.5-pre4","0.9.5-pre5","0.9.5-pre6","0.9.5-pre7","0.9.5-pre8","0.9.5-pre9","0.9.5.1","0.9.5.2","0.9.5.3","0.9.5.4","0.9.5.5"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-5476-xc4j-rqcv/GHSA-5476-xc4j-rqcv.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H"}]}