Ubuntu Security Notice USN-6719-2

Ubuntu Security Notice 6719-2 - USN-6719-1 fixed a vulnerability in util-linux. Unfortunately, it was discovered that the fix did not fully address the issue. This update removes the setgid permission bit from the wall and write utilities. Skyler Ferrante discovered that the util-linux wall command did not filter escape sequences from command line arguments. A local attacker could possibly use this issue to obtain sensitive information.

address command command line escape filter fix issue line linux local notice permission security security notice ubuntu update usn utilities vulnerability wall