# CVE-2026-91803: Security Vulnerability Report – Foxit PDF Editor/Reader Updater DLL Search Path Hijacking

> A local attacker can execute code with elevated privileges by exploiting unsafe DLL loading in the Foxit PDF updater.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 23 Sep 2026
- **Updated:** 23 Sep 2026
- **Also known as:** GHSA-hh85-f5h8-q4pf

## What is CVE-2026-91803?

CVE-2026-91803 is a high-severity vulnerability in Foxit Pdf Editor, published on 23 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A local privilege escalation vulnerability exists in the updater of Foxit PDF Editor/Reader due to unsafe loading of dynamic-link libraries from a user-writable directory during high-privilege operations. A local attacker could exploit this issue to execute code with elevated privileges.

Weakness: CWE-427 (Uncontrolled Search Path Element)

## Which versions are affected by CVE-2026-91803?

It affects 2 products.


Products: Foxit Pdf Editor, Foxit Pdf Reader.

## How do I fix CVE-2026-91803?

No fix has been published for CVE-2026-91803 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-91803 being exploited?

There is no known exploitation of CVE-2026-91803 in the wild and no public exploit code.

## Other vulnerabilities in Foxit Pdf Editor

- [CVE-2022-28104](https://insights.sbomify.com/CVE-2022-28104/): File upload in n/a (critical 9.8)
- [CVE-2022-24954](https://insights.sbomify.com/CVE-2022-24954/): Memory corruption in n/a (critical 9.8)
- [CVE-2022-24955](https://insights.sbomify.com/CVE-2022-24955/): Other in n/a (critical 9.8)
- [CVE-2026-91798](https://insights.sbomify.com/CVE-2026-91798/): Foxit PDF Editor/Reader Updater Privilege Escalation (high 8.8)
- [CVE-2026-91800](https://insights.sbomify.com/CVE-2026-91800/): Foxit PDF Editor installer local privilege escalation (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-91803 and fix it if it is affected.

What it is: CVE-2026-91803 is a high-severity vulnerability in Foxit Pdf Editor, published on 23 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-91803 in the wild and no public exploit code.

Affected product: Foxit Pdf Editor. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-91803/ (Markdown: https://insights.sbomify.com/CVE-2026-91803/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91803
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91803
- OSV: https://osv.dev/vulnerability/CVE-2026-91803

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-91803/
Summaries are generated and may contain mistakes; the official description above is the record.