Instituto Nacional de ciberseguridad. Sección Incibe
Instituto Nacional de Ciberseguridad. Sección INCIBE-CERT

CVE-2026-9256

Gravedad CVSS v4.0:
CRÍTICA
Tipo:
CWE-122 Desbordamiento de búfer basado en memoria dinámica (Heap)
Fecha de publicación:
22/05/2026
Última modificación:
30/06/2026

Descripción

*** Pendiente de traducción *** 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 a restart. Additionally, attackers can execute code on systems with Address Space Layout Randomization (ASLR) disabled or when the attacker can bypass ASLR. <br /> <br /> <br /> Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Productos y versiones vulnerables

CPE Desde Hasta
cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:* 0.1.17 (incluyendo) 0.9.7 (incluyendo)
cpe:2.3:a:f5:nginx_open_source:*:*:*:*:*:*:*:* 1.0.0 (incluyendo) 1.30.1 (incluyendo)
cpe:2.3:a:f5:nginx_open_source:1.31.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:* 37.0.0 (incluyendo) 37.0.1.1 (excluyendo)
cpe:2.3:a:f5:nginx_plus:*:*:*:*:*:*:*:* r32 (incluyendo) r36 (incluyendo)