Newline injection possible into /etc/passwd
Kees Cook discovered that some shadow utilities did not correctly validate user input. A local attacker could exploit this flaw to inject newlines into the /etc/passwd file. If the system was configured to use NIS, this could lead to existing NIS groups or users gaining or losing access to the system, resulting in a denial of service or unauthorized access.
15 February 2011
A security issue affects these releases of Ubuntu and its derivatives:
Newline injection possible into /etc/passwd
Kees Cook discovered that some shadow utilities did not correctly validate user input. A local attacker could exploit this flaw to inject newlines into the /etc/passwd file. If the system was configured to use NIS, this could lead to existing NIS groups or users gaining or losing access to the system, resulting in a denial of service or unauthorized access.
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.
Vulmon