CVE-2015-3245

Vulnerabilidad de lista negra incompleta en la función chfn en libuser en versiones anteriores a 0.56.13-8 y 0.60 en versiones anteriores a 0.60-7, tal como se utiliza en el programa userhelp en el paquete usermode, permite a usuarios locales provocar una denegación de servicio (/etc/passwd corruption) a través de un caracter de nueva línea en el campo GECOS.

It was found that libuser, as used by the chfn userhelper functionality, did not properly filter out newline characters in GECOS fields. A local, authenticated user could use this flaw to corrupt the /etc/passwd file, resulting in a denial-of-service on the system.

The libuser library implements a standardized interface for manipulating and administering user and group accounts. Sample applications that are modeled after applications from the shadow password suite are included in these packages. Two flaws were found in the way the libuser library handled the /etc/passwd file. A local attacker could use an application compiled against libuser to manipulate the /etc/passwd file, which could result in a denial of service or possibly allow the attacker to escalate their privileges to root.