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

CVE-2026-42533

Gravedad CVSS v4.0:
CRÍTICA
Tipo:
CWE-122 Desbordamiento de búfer basado en memoria dinámica (Heap)
Fecha de publicación:
15/07/2026
Última modificación:
16/07/2026

Descripción

*** Pendiente de traducción *** A vulnerability exists in NGINX Plus and NGINX Open Source when a map directive uses regex matching and a string expression references the map&amp;#39;s regex capture variables before referencing the map output variable. Alternatively, the same result could be achieved by using a non-cacheable variable in a string expression under certain conditions. 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 /> Impact:<br /> This vulnerability may allow remote attackers to cause a denial-of-service (DoS) on the NGINX system or to possibly trigger a code execution. There is no control plane exposure; this is a data plane issue only.<br /> <br /> <br /> <br /> <br />  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Referencias a soluciones, herramientas e información