# CVE-2026-91803: Foxit PDF Editor privilege escalation in updater via DLL loading

Source: https://junglewise.ai/threats/cve-2026-91803-a-local-privilege-escalation-vulnerability-exists-in-the-updater  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-23. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-91803 · Severity: high · CVSS 8.8 · Published 2026-09-23

Foxit PDF Editor and Reader include an updater component that loads libraries from a user-writable directory during high-privilege operations, allowing a local attacker to execute code with administrator rights. An attacker with local access could exploit this to gain full system control and install malware or steal sensitive data.

Technologies: [Foxit PDF Editor](https://junglewise.ai/threats/technologies/pdf-editor), [Foxit PDF Reader](https://junglewise.ai/threats/technologies/pdf-reader). Vendors: [Foxit](https://junglewise.ai/threats/vendors/foxit).

## Quick answers

**Is CVE-2026-91803 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91803 being exploited in the wild.

**How severe is CVE-2026-91803?** High severity, with a CVSS score of 8.8, published 23 September 2026.

**Which products and versions are affected?** Foxit PDF Editor 2026.2.0.39747 and all prior 2026.x, 2025.3.0.35737 and all prior 2025.x, 2024.4.1.27687 and all prior 2024.x, 2023.3.0.23028 and all prior 2023.x, 14.0.7.33751 and all prior 14.x, 13.2.6.24111 and earlier on Windows; Foxit PDF Reader 2026.2.0.39747 and earlier on Windows.

**Is there a fix for CVE-2026-91803?** A patch was published on 2026-09-23: Foxit PDF Reader 2026.2.1 and Foxit PDF Editor 2026.2.1/14.0.8 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-91803 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-91803?** Check whether you run Foxit PDF Editor or Foxit PDF Reader at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A DLL preloading/hijacking vulnerability exists in the updater process due to unsafe dynamic library loading from a world-writable directory during privileged operations. The vulnerability requires local access and no user interaction beyond the updater running at elevated privileges. Successful exploitation results in arbitrary code execution with the elevated privileges of the updater process.

## Affected products

- Foxit PDF Reader 2026.2.0.39747 and earlier on Windows
- Foxit PDF Editor 2026.2.0.39747 and all prior 2026.x, 2025.3.0.35737 and all prior 2025.x, 2024.4.1.27687 and all prior 2024.x, 2023.3.0.23028 and all prior 2023.x, 14.0.7.33751 and all prior 14.x, 13.2.6.24111 and earlier on Windows

## Timeline

- 2026-09-23: disclosed: CVE-2026-91803 published and patches released
- 2026-09-23: patched: Foxit PDF Reader 2026.2.1 and Foxit PDF Editor 2026.2.1/14.0.8 released

## References

- [https://www.foxit.com/support/security-bulletins.html](https://www.foxit.com/support/security-bulletins.html)

## Related threats

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