The Java OpenWire protocol marshaller is vulnerable to Remote Code Execution. This vulnerability may allow a remote attacker with network access to either a Java-based OpenWire broker or client to run arbitrary shell commands by manipulating serialized class types in the OpenWire protocol to cause either the client or the broker (respectively) to instantiate any class on the classpath.
Users are recommended to upgrade both brokers and clients to version 5.15.16, 5.16.7, 5.17.6, or 5.18.3 which fixes this issue.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 100.00 |
| Exploitation signal(KEV listed) | ×1.50 |
| Ransomware bonus | +5.00 |
| VPI | 100.00 |
VPI formula vpi-v1
Required Action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
This CVE is referenced in a KISA security bulletin (Korean only).
| Source | CVSS Version | Base Score | Severity | Vector String | Assessment Date |
|---|---|---|---|---|---|
| OSV3rd | 3.1 | 10.0 | CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H/E:H | 04/21/2026 |
| NVDNIST | 3.1 | 10.0 |
The Java OpenWire protocol marshaller is vulnerable to Remote Code Execution. This vulnerability may allow a remote attacker with network access to either a Java-based OpenWire broker or client to run arbitrary shell commands by manipulating serialized class types in the OpenWire protocol to cause either the client or the broker (respectively) to instantiate any class on the classpath. Users are recommended to upgrade both brokers and clients to version 5.15.16, 5.16.7, 5.17.6, or 5.18.3
| CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H |
| 04/20/2026 |