# CVE-2021-3038: GlobalProtect App: Windows VPN kernel driver denial of service (DoS)

> A local attacker can cause a Windows blue screen crash in the GlobalProtect VPN client by sending crafted input to the kernel driver.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 20 Apr 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-9x9w-5fmf-qmhj

## What is CVE-2021-3038?

CVE-2021-3038 is a medium-severity denial of service vulnerability in Palo Alto Networks GlobalProtect App, published on 20 Apr 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A denial-of-service (DoS) vulnerability in Palo Alto Networks GlobalProtect app on Windows systems allows a limited Windows user to send specifically-crafted input to the GlobalProtect app that results in a Windows blue screen of death (BSOD) error. This issue impacts: GlobalProtect app 5.1 versions earlier than GlobalProtect app 5.1.8; GlobalProtect app 5.2 versions earlier than GlobalProtect app 5.2.4.

Weakness: CWE-248 (Uncaught Exception), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-3038?

It affects 1 product.


Products: Paloaltonetworks Globalprotect.

## How do I fix CVE-2021-3038?

No fix has been published for CVE-2021-3038 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-3038 being exploited?

There is no known exploitation of CVE-2021-3038 in the wild and no public exploit code.

## Other vulnerabilities in Palo Alto Networks GlobalProtect App

- [CVE-2025-4232](https://insights.sbomify.com/CVE-2025-4232/): GlobalProtect: Authenticated Code Injection Through Wildcard on macOS (high 8.5)
- [CVE-2021-3057](https://insights.sbomify.com/CVE-2021-3057/): GlobalProtect App: Buffer Overflow Vulnerability When Connecting to Portal or Gateway (high 8.1)
- [CVE-2023-0009](https://insights.sbomify.com/CVE-2023-0009/): GlobalProtect App: Local Privilege Escalation (PE) Vulnerability (high 7.8)
- [CVE-2022-0016](https://insights.sbomify.com/CVE-2022-0016/): GlobalProtect App: Privilege Escalation Vulnerability When Using Connect Before Logon (high 7.4)
- [CVE-2025-0120](https://insights.sbomify.com/CVE-2025-0120/): GlobalProtect App: Local Privilege Escalation (PE) Vulnerability (high 7.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-3038 and fix it if it is affected.

What it is: CVE-2021-3038 is a medium-severity denial of service vulnerability in Palo Alto Networks GlobalProtect App, published on 20 Apr 2021. 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-2021-3038 in the wild and no public exploit code.

Affected product: Palo Alto Networks GlobalProtect App. 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-2021-3038/ (Markdown: https://insights.sbomify.com/CVE-2021-3038/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-3038
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-3038
- OSV: https://osv.dev/vulnerability/CVE-2021-3038

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-3038/
Summaries are generated and may contain mistakes; the official description above is the record.