NULL pointer dereference in NGINX JavaScript - CVE-2026-78222
Published: September 7, 2026
Vulnerability identifier: #VU147229
CSH Severity: Medium
CVSS v4: 8.7 [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]
CVE-ID: CVE-2026-78222
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to null pointer dereference in the ngx_http_js_module module when trusted JavaScript reads Response.statusText from a malformed HTTP response received by ngx.fetch(). A remote attacker can control or influence the fetched HTTP response to cause a denial of service.
This is a data plane issue only and does not expose the control plane.
Affected software
NGINX JavaScript
How to mitigate CVE-2026-78222
Install security update from vendor's website.
NGINX JavaScript - update to 1.0.1