CVE-2013-7423

La función send_dg en resolv/res_send.c en GNU C Library (también conocido como glibc o libc6) en versiones anteriores a 2.20 no reutiliza adecuadamente descriptores de fichero, lo que permite a atacantes remotos mandar consultas DNS a ubicaciones no intencionadas a través de un gran número de peticiones que desencadenan una llamada a la función getaddrinfo.

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.

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.