Use-After-Free in Foxit PDF Editor/Reader Annotations (CVE-2026-91818)
This vulnerability is a use-after-free issue in Foxit PDF Editor/Reader’s JavaScript handling of PDF annotations. The flaw occurs when reentrant page-event processing during annotation enumeration releases the associated page object, which is subsequently accessed, leading to an application crash. Attackers could potentially exploit this flaw to gain unauthorized access or data disclosure. The affected products are Foxit PDF Editor/Reader. Exploitation status is unknown as no public exploit is known.
What to do: Upgrade to the latest version of Foxit PDF Editor/Reader to patch the use-after-free vulnerability. Implement proper memory management and re-check page objects during annotation enumeration to prevent crashes. Monitor for potential re-exploitation and maintain security updates to reduce risk.
| Foxit PDF Editor/Reader | — |
Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.
A use-after-free vulnerability exists in Foxit PDF Editor/Reader’s JavaScript handling of PDF annotations. Reentrant page-event processing during annotation enumeration may release the associated page object, which is subsequently accessed, resulting in an application crash.
A second Foxit PDF Reader annotation use-after-free can allow remote code execution with user interaction (CVE-2026-91818).
ZDI-26-746 covers another annotation use-after-free in Foxit PDF Reader that allows remote code execution if a user opens a malicious file or visits a malicious page. ZDI rated it CVSS 7.8 and assigned CVE-2026-91818. The published advisory does not describe observed exploitation.