It appears Wannacry may have gotten people looking at the SMB functions in Samba on Linux as well. A code-execution bug was detected in all versions of Samba 3.5.0 (released March 2010) and onwards. It is CVE-2017-7494 and there is already a Metasploit module available for attacking Linux servers running Samba for file and print sharing.
A patch is available for this vulnerability. A line can be added to the Samba configuration file as a workaround if the Samba patch cannot be applied, but that change may affect funtionality of Windows machines accessing the share.
Samba team announcement - https://www.samba.org/samba/security/CVE-2017-7494.html