Out-of-bounds read in OpenJ9 - CVE-2026-6918
Published: May 11, 2026
Vulnerability identifier: #VU130954
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-6918
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Eclipse
Affected software:
OpenJ9
OpenJ9
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to out-of-bounds read in Message::deserialize() and MessageBuffer::readData() when processing a crafted TCP message containing an attacker-controlled DataDescriptor._size value. A remote attacker can send a specially crafted TCP message to cause a denial of service.
The issue occurs before protocol-level validation, and no authentication, encryption, or valid JIT compilation request is required. Deployments running without TLS client authentication are affected by default.
How to mitigate CVE-2026-6918
Install security update from vendor's website.