NGINX JavaScript vulnerability_CVE-2026-8711

8.1 / 10

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

NGINX JavaScript has a vulnerability when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable (for example, $http_*, $arg_*, $cookie_*) and a location invoking the ngx.fetch() operation from NGINX JavaScript. An unauthenticated attacker can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to a restart. Additionally, for systems with Address Space Layout Randomization (ASLR) disabled, code execution is possible.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Basic Information

ID CVE-2026-8711

Source f5

Published May 19, 2026 at 14:04

Affected Product

Vendor F5

Product NGINX JavaScript

Version 0.9.4

Affected Versions F5 NGINX JavaScript 0.9.4

CWE Classification

CWE-122

References

my.f5.com /manage/s/article/K000161307

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