CVE-2026-42055 F5 CVE debrief

Who should care

Users of cPanel/WHM with EasyApache 4 should verify and apply the updated packages to prevent potential buffer overflow attacks. This includes administrators and security teams responsible for maintaining and securing their EasyApache 4 environments.

Technical summary

CVE-2026-42055 is a medium-severity vulnerability in ngx_http_proxy_v2_module and ngx_http_grpc_module. The vulnerability is addressed in ea-nginx v1.31.2. The associated nginx module packages (ea-nginx-echo, ea-nginx-headers-more, ea-nginx-njs, ea-nginx-passenger, ea-modsec30-connector-nginx) were also rebuilt against the patched version. This update fixes buffer overflow issues in the affected modules.

Defensive priority

Apply the updated packages for EasyApache 4 to prevent potential buffer overflow attacks. This should be prioritized by administrators and security teams responsible for maintaining and securing their EasyApache 4 environments.

Recommended defensive actions

• Verify and apply the updated packages for EasyApache 4 25.67
• Review and update ea-nginx to v1.31.2
• Update associated nginx module packages
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Evidence notes

The CVE record was published on 2026-06-17T15:16:50.353Z and last modified on 2026-07-02T20:03:31.557Z. The NVD entry is currently 9.2 CRITICAL. This CVE is addressed in EasyApache 4 25.67 security updates, which updates ea-nginx from v1.31.1 to v1.31.2. Users should verify the update and apply it to prevent potential buffer overflow attacks. The associated nginx module packages were also rebuilt against the patched version.

Official resources