Quick answers
- Is CVE-2026-8752 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-8752 being exploited in the wild.
- How severe is CVE-2026-8752?
- Medium severity, with a CVSS score of 5.3, published 17 May 2026.
- Which products and versions are affected?
- H2O.ai H2O-3 up to 7402.
- Is there a fix for CVE-2026-8752?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-8752 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-8752?
- Check whether you run H2O.ai H2O-3 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A critical logic flaw exists in the H2O-3 Rapids engine due to the public exposure of the 'setproperty' primitive via the /99/Rapids endpoint. This endpoint allows unauthenticated users to modify internal system properties across all cluster nodes. An attacker can exploit this to toggle the 'sys.ai.h2o.pojo.import.enabled' property to 'true', bypassing a default security gate designed to prevent the import of potentially malicious Java objects. Once enabled, the attacker can upload a malicious POJO source file and trigger its compilation and instantiation via the /3/ModelBuilders/generic endpoint, resulting in arbitrary code execution within the server environment. The vendor was reportedly contacted but has not provided a patch; remediation involves restricting access to debugging primitives and making security-sensitive properties immutable at runtime.
Affected products
- h2oai h2o-3 up to 7402
Timeline
- 2026-05-17: advisory: Vulnerability disclosed via VulDB and NVD
- 2026-05-17: disclosed: Public exploit details released