Plus 98, an optional package that extends Windows 98 and Windows 98 Second Edition, introduced a data-compression feature called Compressed Folders that was also included in Windows Me. For interoperability with leading third-party compression tools, it provides a password protection option for folders that have been compressed. However, due to a flaw in the package?s implementation, the passwords used to protect the folders are recorded in a file on the user?s system. If an attacker gained access to an affected machine on which password-protected folders were stored, she could learn the passwords and access the files.

The patch will prevent passwords from being written to the user?s system in the future. After applying the patch, it is important to also delete c:windowsdynazip.log to ensure that all previously recorded passwords are deleted.