CVE-2026-111074: JITServer: Pre-authentication remote Denial of Service via integer overflow infinite loop in MessageBuffer::computeRequiredCapacity()

Severity: high (CVSS 8.7 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-21 · updated 2026-10-26
Weakness: CWE-190

Description

In Eclipse OpenJ9 versions prior to 0.63.0, the JITServer component is vulnerable to a pre-authentication remote denial of service. When processing the initial 4-byte length field of an incoming TCP connection, an integer overflow in `MessageBuffer::computeRequiredCapacity()` causes the receiving compilation worker thread to enter an infinite loop consuming ~100% CPU. An unauthenticated remote attacker can exploit this by opening a small number of crafted TCP connections to exhaust the entire worker thread pool, silently halting compilation services for all connected client JVMs.

Affected products

The Eclipse Foundation Eclipse OpenJ9: from 0.8.0 before 0.63 — fixed in 0.63

How to fix

Upgrade to a fixed version: The Eclipse Foundation Eclipse OpenJ9 0.63. Check the vendor advisory for mitigations.

References

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