Microsoft today pushed out 13 security updates to fix at least 39 separate vulnerabilities in its various Windows operating systems and software. Five of the updates fix flaws that allow hackers or malware to break into vulnerable systems without any help from the user, save for perhaps visiting a hacked Web site.

The bulk of the security holes plugged in this month’s Patch Tuesday reside in either Internet Explorer or in Microsoft’s flagship browser — Edge. As security firm Shavlik notes, Microsoft’s claim that Edge is more secure than IE seems to be holding out, albeit not by much. So far this year, Shavlik found, Edge has required 19 fixes versus IE’s 27.

Windows users who get online with a non-Microsoft browser still need to get their patches on: Ten of the updates affect Windows — including three other critical updates from Microsoft. As always, Qualys has a readable post about the rest of the Microsoft patches. If you experience any issues with the Windows patches, please share your experience in the comments below.

As it is known to do on patch Tuesday, Adobe issued security updates for its Reader and Acrobat software. Alas, there appears to be no update for Adobe’s Flash Player plugin as per usual on Patch Tuesday. However, an Adobe spokesperson told KrebsOnSecurity that the company will be issuing a Flash Player update on Thursday morning.