# CVE-2026-42055

> NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_proxy_v2_module and ngx_http_grpc_module modules. This vulnerability exists when the proxy_http_version to 2 or grpc_pass directives are used to proxy HTTP/2 traffic, the ignore_invalid_headers directive is set to off, and the large_client_header_buffers directive size is larger than 2 megabytes. A remote, unauthenticated attacker, along with conditions beyond their control, could send large headers while creating an upstream request. This may cause a heap-based buffer overflow in the NGINX worker process leading to a restar

- **CVSS:** 8.1 (HIGH)
- **EPSS:** 1.8%
- **CWE:** CWE-122

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-42055
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