CVE-2026-6918 Denial of service in Eclipse OpenJ9

What is CVE-2026-6918?

CVE-2026-6918 is a high-severity denial of service vulnerability in Eclipse OpenJ9, published on 5 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Eclipse Open9J versions 0.21 to 0.58, a pre-authentication remote attacker can crash JITServer by sending a 32-byte crafted TCP message.

Weakness: CWE-1286, CWE-125

Which versions are affected by CVE-2026-6918?

It affects 1 product.

Products include Eclipse Openj9.

How do I fix CVE-2026-6918?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-6918 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-6918 exists.

Other vulnerabilities in Eclipse OpenJ9

• CVE-2021-41035 Security feature bypass in Eclipse OMR Critical 9.8
• CVE-2020-27221 Memory corruption in Eclipse OpenJ9 Critical 9.8
• CVE-2019-11772 Memory corruption in Eclipse OpenJ9 Critical 9.8
• CVE-2018-12547 Memory corruption in Eclipse OpenJ9 Critical 9.8
• CVE-2018-12549 Null dereference in Eclipse OpenJ9 Critical 9.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-q393-vr4c-969r, UBUNTU-CVE-2026-6918.