Over the last couple of years, I've developed a fairly keen interest in Penetration Testing & Information Security. Throughout this time, I've acquired (and accumulated) a range of different devices with network capabilities, primarily, in an effort to learn more about various security auditing techniques. Below is an excerpt of an
nmap scan of one such device:
Host script results: | smb-os-discovery: | OS: Windows 10 Home 10240 (Windows 10 Home 6.3) | NetBIOS computer name: MARK | Workgroup: WORKGROUP |_ System time: 2015-09-24T23:38:38-06:00 | smb-security-mode: | Account that was used for smb scripts: <blank> | User-level authentication | SMB Security: Challenge/response passwords supported |_ Message signing disabled (dangerous, but default) |_smbv2-enabled: Server supports SMBv2 protocol
My question is specifically regarding the following statement:
Message signing disabled (dangerous, but default).
What is message signing; what is the danger?
Any examples of working exploits would be appreciated.