SRC-2021-0024 : Foxit Reader Field OnFocus event Use-After-Free Remote Code Execution Vulnerability



CVSS Score:

8.8, (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Affected Vendors:


Affected Products:

Foxit Reader

Vulnerability Details:

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Foxit PDF Reader. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.

The specific flaw exists within the handling of Field objects. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this vulnerability to execute code in the context of the current process.

Vendor Response:

Foxit has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline:

  • 2021-08-20 – Sent to and verified by Foxit
  • 2021-10-12 – Coordinated public release of advisory


This vulnerability was discovered by Steven Seeley of Qihoo 360 Vulcan Team