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.
Affected products
eclipse: openj9
References7
- github.com/eclipse-openj9/openj9/security/advisories/GHSA-q393-… ExploitVendor Advisory
- github.com/eclipse-openj9/openj9/security/advisories/GHSA-q393-… ExploitVendor Advisory
- github.com/eclipse-openj9/openj9/pull/23793 Issue TrackingPatch
- access.redhat.com/errata/RHSA-2026:22328
- access.redhat.com/security/cve/CVE-2026-6918
- bugzilla.redhat.com/show_bug.cgi?id=2466741
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-6918.…
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
8.7
HIGH
Score source: CNA
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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 45 · as of 13 November 2026
- CWE
- CWE-125CWE-1286
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.