# CVE-2003-0567: Denial of service in n/a

> Remote attackers can cause a denial of service on Cisco IOS devices by sending specific IPv4 packets that fill the interface input queue.

- **Severity:** High 7.8 (`AV:N/AC:L/Au:N/C:N/I:N/A:C`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 25 Jul 2003
- **Updated:** 8 Aug 2024
- **Also known as:** GHSA-c4c9-f467-hxxv

## What is CVE-2003-0567?

CVE-2003-0567 is a high-severity denial of service vulnerability in Cisco Ios, published on 25 Jul 2003. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Cisco IOS 11.x and 12.0 through 12.2 allows remote attackers to cause a denial of service (traffic block) by sending a particular sequence of IPv4 packets to an interface on the device, causing the input queue on that interface to be marked as full.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2003-0567?

It affects 3 products.


Products: Cisco Ios, Cisco Ons 15454 Optical Transport Platform, Cisco Optical Networking Systems Software.

## How do I fix CVE-2003-0567?

No fix has been published for CVE-2003-0567 yet. Limit exposure of the affected software until one is available.

## Is CVE-2003-0567 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2003-0567 exists.

Public exploit code:

- Cisco IOS - IPv4 Packets Denial of Service (exploitdb)
- Cisco IOS - 'cisco-bug-44020.c' IPv4 Packet Denial of Service (exploitdb)
- Cisco IOS - using hping Remote Denial of Service (exploitdb)

## Other vulnerabilities in Cisco Ios

- [CVE-2017-12240](https://insights.sbomify.com/CVE-2017-12240/): Cisco IOS and IOS XE Software DHCP Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2017-3881](https://insights.sbomify.com/CVE-2017-3881/): Cisco IOS and IOS XE Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2018-0167](https://insights.sbomify.com/CVE-2018-0167/): Cisco IOS, XR, and XE Software Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2017-6736](https://insights.sbomify.com/CVE-2017-6736/): Cisco IOS and IOS XE Software SNMP Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2017-6737](https://insights.sbomify.com/CVE-2017-6737/): Cisco IOS and IOS XE Software SNMP Remote Code Execution (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2003-0567 and fix it if it is affected.

What it is: CVE-2003-0567 is a high-severity denial of service vulnerability in Cisco Ios, published on 25 Jul 2003. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2003-0567 exists.

Affected product: Cisco Ios. 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-2003-0567/ (Markdown: https://insights.sbomify.com/CVE-2003-0567/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2003-0567
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2003-0567
- OSV: https://osv.dev/vulnerability/CVE-2003-0567

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From sbomify Insights: https://insights.sbomify.com/CVE-2003-0567/
Summaries are generated and may contain mistakes; the official description above is the record.