{"id":"UBUNTU-CVE-2026-27830","details":"c3p0, a JDBC Connection pooling library, 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`. The 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`. Although 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. The `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. c3p0-0.12.0+ 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. c3p0 additionally enforces the new mchange-commons-java `com.mchange.v2.naming.nameGuardClassName` to prevent injection of unexpected, potentially remote JNDI names. There is no supported workaround for versions of c3p0 prior to 0.12.0.","modified":"2026-08-18T22:01:26.876171174Z","published":"2026-02-26T01:16:00Z","related":["USN-8642-1"],"upstream":["CVE-2026-27830"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-27830"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-27830"},{"type":"REPORT","url":"https://github.com/swaldman/c3p0/commit/e14cbd8166e423e2e9a9d6f08b2add3433492d6e"},{"type":"REPORT","url":"https://github.com/swaldman/c3p0/security/advisories/GHSA-5476-xc4j-rqcv"},{"type":"REPORT","url":"https://mogwailabs.de/en/blog/2025/02/c3p0-you-little-rascal"},{"type":"REPORT","url":"https://www.mchange.com/projects/c3p0/#configuring_security"},{"type":"REPORT","url":"https://www.mchange.com/projects/c3p0/#security-note"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8642-1"}],"affected":[{"package":{"name":"c3p0","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/c3p0?arch=source&distro=esm-apps-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.1.2-9+deb8u1ubuntu0.16.04.1~esm2"}]}],"versions":["0.9.1.2-9","0.9.1.2-9+deb8u1build0.16.04.1","0.9.1.2-9+deb8u1ubuntu0.16.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libc3p0-java","binary_version":"0.9.1.2-9+deb8u1ubuntu0.16.04.1~esm2"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-27830.json"}},{"package":{"name":"c3p0","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/c3p0?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.9.1.2-10ubuntu0.20.04.1+esm1"}]}],"versions":["0.9.1.2-10","0.9.1.2-10ubuntu0.20.04.1"],"ecosystem_specific":{"binaries":[{"binary_version":"0.9.1.2-10ubuntu0.20.04.1+esm1","binary_name":"libc3p0-java"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-27830.json"}},{"package":{"name":"c3p0","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/c3p0?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.9.1.2-10ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"libc3p0-java","binary_version":"0.9.1.2-10ubuntu2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-27830.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"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}