# CVE-2026-20064: Null dereference in Cisco Secure Firewall Threat Defense (FTD) Software

> A local attacker with low privileges can cause a Cisco Secure Firewall Threat Defense device to reload, resulting in a denial of service.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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:** 4 Mar 2026
- **Updated:** 4 Mar 2026
- **Also known as:** GHSA-h526-7r62-gcj9

## What is CVE-2026-20064?

CVE-2026-20064 is a medium-severity vulnerability in Cisco Secure Firewall Threat Defense, published on 4 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in of Cisco Secure Firewall Threat Defense (FTD) Software could allow an authenticated, local attacker to cause the device to unexpectedly reload, causing a denial of service (DoS) condition.

 This vulnerability is due to improper validation of user-supplied input. An attacker with a low-privileged account could exploit this vulnerability by using crafted commands at the CLI prompt. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-20064?

It affects 1 product.


Products: Cisco Secure Firewall Threat Defense.

## How do I fix CVE-2026-20064?

No fix has been published for CVE-2026-20064 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-20064 being exploited?

There is no known exploitation of CVE-2026-20064 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Secure Firewall Threat Defense

- [CVE-2024-20412](https://insights.sbomify.com/CVE-2024-20412/): Hardcoded credentials in Cisco Firepower Threat Defense Software (critical 9.3)
- [CVE-2024-20330](https://insights.sbomify.com/CVE-2024-20330/): Memory corruption in Cisco Firepower Threat Defense Software (high 8.6)
- [CVE-2024-20339](https://insights.sbomify.com/CVE-2024-20339/): Cisco Firepower Threat Defense Software for Firepower 2100 Series TLS Denial of Service Vulnerability (high 8.6)
- [CVE-2024-20351](https://insights.sbomify.com/CVE-2024-20351/): Cisco Firepower Threat Defense Software Snort Firewall Denial of Service Vulnerability (high 8.6)
- [CVE-2023-20083](https://insights.sbomify.com/CVE-2023-20083/): Denial of service in Cisco Firepower Threat Defense Software (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-20064 and fix it if it is affected.

What it is: CVE-2026-20064 is a medium-severity vulnerability in Cisco Secure Firewall Threat Defense, published on 4 Mar 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-2026-20064 in the wild and no public exploit code.

Affected product: Cisco Secure Firewall Threat Defense. 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-2026-20064/ (Markdown: https://insights.sbomify.com/CVE-2026-20064/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-20064
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-20064
- OSV: https://osv.dev/vulnerability/CVE-2026-20064

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-20064/
Summaries are generated and may contain mistakes; the official description above is the record.