The appearance and disappearance of a Windows XP installation snafu indicates that Microsoft patched a critical vulnerability in XP"s still-unfinished Service Pack 3 (SP3) weeks before it fixed any other version of Windows. The glitch, which sent some PCs into an endless round of reboots, was strangely similar to one faced by Vista users in February. Attackers have already tried to exploit that bug, which was patched last Tuesday -- as it turned out, two weeks after the newest build of Windows XP SP3 was released with the flaw fixed.
According to reports from multiple users on a Microsoft support newsgroup, PCs began rebooting immediately after they had been updated to SP3. "I have just updated my pc from xp sp2 to sp3," said a user identified as "yaojinglin" in a message to a SP3 support forum last Thursday. "The installation was successful, but when I reboot my pc after the installation finished, my pc started to reboot again and again."
On the XP SP3 support threads, a Microsoft representative named Shashank Bansal stepped into the rebooting discussion, which was beginning to seem as endless as the rebooting itself. Bansal asked for more information, then offered an explanation: "This issue happens with 3311 build of XP SP3. It happens because KB948590 stops installation of SP3 version of gdi32.dll on the system due to file-version differences."