CVE-2015-1473

El macro ADDW en stdio-common/vfscanf.c en la libraría GNU C (también conocida como glibc o libc6) anterior a 2.21 no considera correctamente el tamaño de tipos de datos durante una decisión de la gestión de riesgos para utilizar en la función alloca, lo que podría permitir atacantes dependientes de contexto causar una denegación de servicio (violación de segmentación) o sobrescribir localizaciones de memoria más allá del límite de la pila a través de una línea larga que contiene caracateres anchas que se manejen incorrectamente en una llamada wscanf.

A stack overflow flaw was found in glibc's swscanf() function. An attacker able to make an application call the swscanf() function could use this flaw to crash that application or, potentially, execute arbitrary code with the permissions of the user running the application.

The glibc packages provide the standard C libraries, POSIX thread libraries, standard math libraries, and the Name Server Caching Daemon used by multiple programs on the system. Without these libraries, the Linux system cannot function correctly. It was discovered that the nss_files backend for the Name Service Switch in glibc would return incorrect data to applications or corrupt the heap. A local attacker could potentially use this flaw to execute arbitrary code on the system. It was discovered that, under certain circumstances, glibc's getaddrinfo() function would send DNS queries to random file descriptors. An attacker could potentially use this flaw to send DNS queries to unintended recipients, resulting in information disclosure or data loss due to the application encountering corrupted data.