# CVE-2026-3777: Use after free of view cache in Foxit PDF Editor/Reader

> Crafted JavaScript in a PDF can trigger a use-after-free in the view cache, potentially allowing arbitrary code execution in Foxit PDF Editor and Reader.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 1 Apr 2026
- **Updated:** 2 Apr 2026
- **Also known as:** GHSA-6xgc-8m9r-qvgm

## What is CVE-2026-3777?

CVE-2026-3777 is a medium-severity use after free vulnerability in Foxit Pdf Editor, published on 1 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

The application does not properly validate the lifetime and validity of internal view cache pointers after JavaScript changes the document zoom and page state. When a script modifies the zoom property and then triggers a page change, the original view object may be destroyed while stale pointers are still kept and later dereferenced, which under crafted JavaScript and document structures can lead to a use-after-free condition and potentially allow arbitrary code execution.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2026-3777?

It affects 2 products.


Products: Foxit Pdf Editor, Foxit Pdf Reader.

## How do I fix CVE-2026-3777?

No fix has been published for CVE-2026-3777 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-3777 being exploited?

There is no known exploitation of CVE-2026-3777 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-2026-3777 and fix it if it is affected.

What it is: CVE-2026-3777 is a medium-severity use after free vulnerability in Foxit Pdf Editor, published on 1 Apr 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-3777 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-2026-3777/ (Markdown: https://insights.sbomify.com/CVE-2026-3777/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-3777
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-3777
- OSV: https://osv.dev/vulnerability/CVE-2026-3777

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-3777/
Summaries are generated and may contain mistakes; the official description above is the record.