In recent days, Windows Update (WU) started altering files on users’ systems without displaying any dialog box to request permission. The only files that have been reportedly altered to date are nine small executables on XP and nine on Vista that are used by WU itself. Microsoft is patching these files silently, even if auto-updates have been disabled on a particular PC.
It’s surprising that these files can be changed without the user’s knowledge. The Automatic Updates dialog box in the Control Panel can be set to prevent updates from being installed automatically. However, with Microsoft’s latest stealth move, updates to the WU executables seem to be installed regardless of the settings — without notifying users.
When users launch Windows Update, Microsoft’s online service can check the version of its executables on the PC and update them if necessary. What’s unusual is that people are reporting changes in these files although WU wasn’t authorized to install anything.