libexpat is a fast streaming XML parser. Alongside libxml2, Expat is one of the most widely used software libre XML parsers written in C, precisely C99. It is cross-platform and licensed under the MIT license.

Expat 2.4.3 has been released earlier today. Besides two minor fixes to the build system, this release is about security fixes. There is a total of 8 CVEs fixed, all related to fixed-size integer math (integer overflow and invalid shifts) near memory allocation. Impact is denial of service, or more.

• CVE-2021-45960
• CVE-2021-46143
• CVE-2022-22822
• CVE-2022-22823
• CVE-2022-22824
• CVE-2022-22825
• CVE-2022-22826
• CVE-2022-22827

For more details, please check out the change log.

If you maintain Expat packaging or a bundled copy of Expat or a pinned version of Expat somewhere, please update to 2.4.3. Thank you!

Sebastian Pipping