Add or Remove Programs entry for Windows XP Hotfix - KB888113. This update should not be uninstalled.

Vulnerability details this update fixed:

"A remote code execution vulnerability exists in the Hyperlink Object Library. This problem exists because of an unchecked buffer while handling hyperlinks. An attacker could exploit the vulnerability by constructing a malicious hyperlink which could potentially lead to remote code execution if a user clicks a malicious link within a Web site or e-mail message. An attacker who successfully exploited this vulnerability could take complete control of the affected system. User interaction is required to exploit this vulnerability."