# CVE-2026-9256

> NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerability exists when a rewrite directive uses a regex pattern with distinct, overlapping Perl-Compatible Regular Expression (PCRE) captures (for example, ^/((.*))$) and a replacement string that references multiple such captures (for example, $1$2) in a redirect or arguments context. An unauthenticated attacker along with conditions beyond their control can exploit this vulnerability by sending crafted HTTP requests. This may cause a heap buffer overflow in the NGINX worker process leading to

- **CVSS:** 8.1 (HIGH)
- **EPSS:** 0.2%
- **CWE:** CWE-122

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-9256
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