Exactly one week ago, an anonymous user shared a link on the 4chan message board. This link led to a file archive of about 3GB, where parts of the source code of Windows XP and Windows Server 2003 are located. Although these Windows versions have been out of date for years, the open source code poses a threat to current systems.
Windows XP source code became a collection
As already mentioned, at the beginning a link was distributed which leads to an archive containing about 3GB of source code of Windows XP and Windows Server 2003. After other users have seen this archive, it was extended with other leaked parts of the source code. So this archive, which was initially only 3GB in size, gradually became a 41GB collection.
According to the initial assessments of Windows experts and security researchers, these published files are indeed original source code. The file extension cab is an archive. If you unpack the single archives you get access to several cpp and header files.
Dangers from published code
As soon as attackers have access to actually used Windows XP source code, it is likely that new vulnerabilities will be discovered. Through these vulnerabilities that the attackers can discover, new exploits are written that can exploit exactly these vulnerabilities.
Although Windows XP and Windows Server 2003 have been out of date for several years, these versions are still in use in some cases. It is often reported that outdated operating systems are still in use, because a changeover would be too expensive or too time-consuming. Some time ago Microsoft announced the support end for Windows 7, this is exactly where the discussion arose, since many authorities run all systems on Windows 7.
Beside the systems that actually still use Windows XP or Server 2003 there is also a danger for current systems with Windows 10, because the probability that parts of the Windows XP source code are also included in Windows 10 is very high. If a vulnerability is found in the public source code of Windows XP, it is quite possible that a similar vulnerability is included in Windows 10.
To protect yourself against such vulnerabilities and the associated attacks, you should update your systems regularly. Most updates are intended to close current security holes. Therefore updates should always be made.