Bug in Samba allows remote root code execution

The developers behind Samba, the software used in Linux for file sharing via Windows’ SMB protocol, hastily released a patch on Friday due to a serious security problem. All 4.xx versions were vulnerable.

The vulnerability allows a browser to overwrite packets in the nmbd server, a daemon that can communicate with NetBIOS. This makes it possible to execute root code remotely, Samba announced.

Samba has marked versions 4.1.11 and 4.0.21 as security releases, just two days after version 4.0.20 was released. In addition, patches have also become available for older versions. Samba says that system administrators should install the patch as soon as possible. For those who cannot, there is a workaround available. It simply means that the nmbd server is not allowed to run.

This is not the first time that a serious vulnerability has been found in Samba. Two years ago, malicious parties could also run root code remotely. At the time, all versions since 2003 were vulnerable.