# CVE-2026-27830: c3p0 — Fixed in 0.12.0 ☕ Maven Not in CISA KEV # CVE-2026-27830 — c3p0 [Fix: swaldman/c3p0@e14cbd8](https://github.com/swaldman/c3p0/commit/e14cbd8166e423e2e9a9d6f08b2add3433492d6e) CVE-2026-27830 is a Code Injection vulnerability in com.mchange:c3p0. A fix is available for com.mchange:c3p0 — see the affected versions and patch details below. c3p0 vulnerable to Remote Code Execution via unsafe deserialization of userOverridesAsString property Also known as[GHSA-5476-xc4j-rqcv](/vulnerability/GHSA-5476-xc4j-rqcv) Published Feb 26, 2026 Updated Oct 28, 2026 Affected 1 pkg Patched 1 / 1 Exploits None indexed Exploitation data as of Nov 9, 2026 · OSV.dev, NVD, FIRST.org (EPSS) ## Exploitation Status ### No confirmed exploitation observed yet - A successful exploit gives an attacker total control of the affected component, not partial access. - CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment. Exploitation and automatability from CISA’s SSVC triage for CVE-2026-27830. ## EPSS Exploitation Probability [via FIRST.org ↗](https://www.first.org/epss/) 0.6%probability of exploitation in next 30 days Lower Risk0.00% Lower risk than most CVEs49th percentile — riskier than 49% of all scored CVEsHighest risk 0.00%0.91%1.83%2.74%0.2%0.6%May 26Sep 26Nov 26 Probability of exploitation in the next 30 days, from [FIRST.org EPSS](https://www.first.org/epss/). ## Real-World Exposure 1 pkg affected ☕`com.mchange:c3p0` Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems. ## Description #### Impact c3p0 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>`. 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. #### Patches 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. Those parameters are documented [here](https://www.mchange.com/projects/c3p0/#configuring_security). c3p0 additionally enforces the new mchange-commons-java `com.mchange.v2.naming.nameGuardClassName` to prevent injection of unexpected, potentially remote JNDI names. #### Workarounds Users should upgrade to c3p0-0.12.0 or above. There is no supported workaround for earlier versions of c3p0. #### References [c3p0, you little rascal — Hans-Martin Münch](https://mogwailabs.de/en/blog/2025/02/c3p0-you-little-rascal/) [c3p0 documentation, security note](https://www.mchange.com/projects/c3p0/#security-note) [c3p0 documentation, configuring security](https://www.mchange.com/projects/c3p0/#configuring_security) ## Affected Packages 1 total 1 fixed Ecosystem Package Vulnerable range Fix ☕Maven `com.mchange:c3p0` all versions 0.12.0`com.mchange:c3p0:0.12.0` ## Detection & mitigation playbook Open-source dependency 1. ### Detect Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.mchange:c3p0, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version. 2. ### Fix Update com.mchange:c3p0 to 0.12.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-27830 is resolved across your whole dependency graph. 3. ### Workarounds Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does. ## Fixing This On Your OS If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project. Red HatImportant Red Hat has evaluated this vulnerability as having an Important security impact because successful exploitation allows arbitrary code execution with the permissions of the application process, though it requires existing privileges or an adjacent network position to supply malicious data sources. In Red Hat enterprise… Product Fixed in Advisory Red Hat build of Apache Camel 4.14.4 for Spring Boot 3.5.11 `com.mchange/c3p0` [RHSA-2026:3890](https://access.redhat.com/errata/RHSA-2026:3890) Red Hat Build of Debezium 3.2 `com.mchange/c3p0` [RHSA-2026:4285](https://access.redhat.com/errata/RHSA-2026:4285) Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7 `eap7-hibernate-0:5.1.17-5.Final_redhat_00006.1.ep7.el7` [RHSA-2026:73976](https://access.redhat.com/errata/RHSA-2026:73976) Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7 `eap7-hibernate-0:5.3.39-1.Final_redhat_00001.1.el7eap` [RHSA-2026:73644](https://access.redhat.com/errata/RHSA-2026:73644) Red Hat JBoss Enterprise Application Platform 8.1.6.GA `org.hibernate.orm/hibernate-core:6.6.48.Final-redhat-00001` [RHSA-2026:18059](https://access.redhat.com/errata/RHSA-2026:18059) Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8 `eap8-hibernate-0:6.6.48-1.Final_redhat_00001.1.el8eap` [RHSA-2026:18054](https://access.redhat.com/errata/RHSA-2026:18054) Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9 `eap8-hibernate-0:6.6.48-1.Final_redhat_00001.1.el9eap` [RHSA-2026:18055](https://access.redhat.com/errata/RHSA-2026:18055) Red Hat Satellite 6.18 for RHEL 9 `candlepin-0:4.6.6-1.el9sat` [RHSA-2026:28385](https://access.redhat.com/errata/RHSA-2026:28385) ## Frequently Asked Questions \### Impact c3p0 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>\`. 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 ap O3 Security · Impact-Aware SCA ### Is CVE-2026-27830 in your dependencies? Find it across Maven, including transitive dependencies. [Scan my dependencies](/book-demo) [How O3 SCA works](/impact-aware-sca)