CVE-2021-34963: 
Foxit PDF Reader vulnerability analysis and mitigation

CVE-2021-34963 is a Use-After-Free vulnerability affecting Foxit PDF Editor that was discovered in 2021. The vulnerability allows remote attackers to execute arbitrary code on affected installations of the software. The issue specifically exists within the handling of PolyLine Annotation objects, where the application fails to validate the existence of an object prior to performing operations on it (ZDI Advisory).

The vulnerability has been assigned a CVSS score of 7.8 (High) with the following vector: AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The specific flaw exists within the handling of Annotation objects, where the application fails to properly validate the existence of an object before performing operations on it. This Use-After-Free condition can be exploited to execute arbitrary code in the context of the current process (ZDI Advisory).

If successfully exploited, this vulnerability allows attackers to execute arbitrary code in the context of the current process on affected installations of Foxit PDF Editor. However, user interaction is required as the target must visit a malicious page or open a malicious file for the exploit to be successful (ZDI Advisory).

Foxit has released a security update to address this vulnerability. Users are advised to update their Foxit PDF Editor installations to the latest version available through the vendor's website (ZDI Advisory).