CVE-2026-8711
Heap Buffer Overflow in NGINX JavaScript
Publication date: 2026-05-19
Last updated on: 2026-05-19
Assigner: F5 Networks
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nginx | nginx | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-122 | A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in NGINX JavaScript when the js_fetch_proxy directive is configured with at least one client-controlled NGINX variable, such as $http_*, $arg_*, or $cookie_*, and a location uses the ngx.fetch() operation.
An unauthenticated attacker can exploit this by sending specially crafted HTTP requests, which may cause a heap buffer overflow in the NGINX worker process, potentially leading to a process restart.
Furthermore, on systems where Address Space Layout Randomization (ASLR) is disabled, this vulnerability could allow the attacker to execute arbitrary code.
How can this vulnerability impact me? :
The vulnerability can impact you by causing the NGINX worker process to crash and restart, leading to potential denial of service.
On systems without ASLR enabled, an attacker could exploit this vulnerability to execute arbitrary code, which could compromise the security and integrity of your system.