# CVE-2018-0230: Denial of service in Cisco Firepower 2100 Series Security Appliances

> Remote attackers can cause a denial of service on Cisco Firepower 2100 appliances by sending malicious fragmented IP packets, requiring a manual reload.

- **Severity:** High 8.6 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Apr 2018
- **Updated:** 29 Nov 2024
- **Also known as:** GHSA-wwrh-gqqp-fjq5

## What is CVE-2018-0230?

CVE-2018-0230 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 19 Apr 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the internal packet-processing functionality of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Security Appliances could allow an unauthenticated, remote attacker to cause an affected device to stop processing traffic, resulting in a denial of service (DoS) condition. The vulnerability is due to the affected software improperly validating IP Version 4 (IPv4) and IP Version 6 (IPv6) packets after the software reassembles the packets (following IP Fragmentation). An attacker could exploit this vulnerability by sending a series of malicious, fragmented IPv4 or IPv6 packets to an affected device. A successful exploit could allow the attacker to cause Snort processes on the affected device to hang at 100% CPU utilization, which could cause the device to stop processing traffic and result in a DoS condition until the device is reloaded manually. This vulnerability affects Cisco Firepower Threat Defense (FTD) Software Releases 6.2.1 and 6.2.2, if the software is running on a Cisco Firepower 2100 Series Security Appliance. Cisco Bug IDs: CSCvf91098.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2018-0230?

It affects 2 products.


Products: Cisco Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense.

## How do I fix CVE-2018-0230?

No fix has been published for CVE-2018-0230 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0230 being exploited?

There is no known exploitation of CVE-2018-0230 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Adaptive Security Appliance Software

- [CVE-2025-20333](https://insights.sbomify.com/CVE-2025-20333/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow (critical 9.9, exploited in the wild)
- [CVE-2016-6366](https://insights.sbomify.com/CVE-2016-6366/): Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2026-20349](https://insights.sbomify.com/CVE-2026-20349/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection (high 8.6, exploited in the wild)
- [CVE-2024-20353](https://insights.sbomify.com/CVE-2024-20353/): Cisco ASA and FTD Denial of Service (high 8.6, exploited in the wild)
- [CVE-2016-6367](https://insights.sbomify.com/CVE-2016-6367/): Cisco Adaptive Security Appliance (ASA) CLI Remote Code Execution (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-0230 and fix it if it is affected.

What it is: CVE-2018-0230 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 19 Apr 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-0230 in the wild and no public exploit code.

Affected product: Cisco Adaptive Security Appliance Software. 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-2018-0230/ (Markdown: https://insights.sbomify.com/CVE-2018-0230/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0230
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0230
- OSV: https://osv.dev/vulnerability/CVE-2018-0230

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From sbomify Insights: https://insights.sbomify.com/CVE-2018-0230/
Summaries are generated and may contain mistakes; the official description above is the record.