Yo que pretendía pasar una semana santa calmado … Resulta que acaban de soltar 3 nuevas vulnerabilidades que afectan a productos de cisco. Ademas de las chungas … «A remote attacker could exploit some of these vulnerabilities to take control of an affected system.»
Cisco-sa-20180328-xesc: Esta me la he tenido que leer varias veces… porque era algo como … no puede ser …pero resulta que si.
«The vulnerability is due to an undocumented user account with privilege level 15 that has a default username and password.». en fin …Afecta a todos los dispositivos que tengan la versión Cisco IOS XE Software Release 16.x. . Cualquier otra version no es vulnerable.
cisco-sa-20180328-smi2: Esta es mas normal …
«An attacker could exploit this vulnerability by sending a crafted Smart Install message to an affected device on TCP port 4786. A successful exploit could allow the attacker to cause a buffer overflow on the affected device, which could have the following impacts:
Triggering a reload of the device
Allowing the attacker to execute arbitrary code on the device
Causing an indefinite loop on the affected device that triggers a watchdog crash
»
Como odio estas cosas … en vez de poner una lista con las versiones afectadas te hacen usar una herramienta para ir comprobándolas una a una.
Además hay que mirar si tienes Smart install client feature enabled … vamos que, como para unas prisas.
To determine whether a device is configured with the Smart Install client feature enabled, use the show vstack config privileged EXEC command on the Smart Install client. An output of Role: Client and Oper Mode: Enabled or Role: Client (SmartInstall enabled) from the show vstack config command confirms that the feature is enabled on the device.
Cisco-sa-20180328-qos: otra que tiene una pinta mas razonable …
«The vulnerability is due to incorrect bounds checking of certain values in packets that are destined for UDP port 18999 of an affected device.»
show udp command in the CLI.
The device may be affected by this vulnerability if the command returns output similar to the following example:
Router> show udp
Proto Remote Port Local Port In Out Stat TTY OutputIF
17 0.0.0.0 0 –any– 18999 0 0 11 0
Todo muy bonito … salvo que tengas mas de 1000 equipos … que semana me espera …