Software Engineering Institute

DynaZip is a popular compression library for the Microsoft Windows platform. A bounds checking deficiency in DynaZip may allow a buffer overflow. An attacker can exploit this vulnerability by creating a zip archive containing files with long names. Depending on the version of DynaZip and the length of the file names, a buffer overflow can occur when a user accesses a specially crafted archive.

According to InnerMedia, DynaZip versions prior to and including 5.00.03 are vulnerable. DynaZip version 5.00.04 and later, as well as DynaZip Max Secure version 6.00.01 and later are not affected by this vulnerability.

The DynaZip library is used in a wide variety of applications. Software developers should check their applications to ensure they are using a non-vulnerable version of library. In addition, users are encouraged to contact their software vendors if they suspect they are vulnerable.

If a remote attacker can persuade a user to access a specially crafted zip file, the attacker may be able to execute arbitrary code on that user's system, possibly with elevated privileges.

Upgrade DynaZip

Inner Media customers are encouraged to upgrade to an unaffected version of DynaZip.

Inner Media's update and upgrade policy states:

Any registered licensed user of DynaZip may update any major revision level of DynaZip to any minor revision level update within then same major revision for FREE. For example; DynaZip version 5.00.03 can be updated to version 5.00.04 for FREE. Any upgrade from one major revision level of DynaZip to another major revision level is offered at a reduced cost to any licensee. For example an upgrade from DynaZip version 4.00.04 to version 5.00.04 would incur a charge.