CVE-2021-27645

El demonio de almacenamiento en caché nameserver (nscd) en el GNU C Library (también se conoce como glibc o libc6) versiones 2.29 hasta 2.33, cuando se procesa una petición de búsqueda de netgroup, puede cometer un fallo debido a una doble liberación, potencialmente resultando en un servicio degradado o denegación de servicio en el sistema local. Esto está relacionado con el archivo netgroupcache.c

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6), when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system.

Jan Engelhardt, Tavis Ormandy, and others discovered that the GNU C Library iconv feature incorrectly handled certain input sequences. An attacker could possibly use this issue to cause the GNU C Library to hang or crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. Jason Royes and Samuel Dytrych discovered that the GNU C Library incorrectly handled signed comparisons on ARMv7 targets. A remote attacker could use this issue to cause the GNU C Library to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS.