# CVE-2018-0256: Denial of service in Cisco Packet Data Network Gateway

> Unauthenticated remote attackers can cause a denial of service by sending crafted packets to Cisco Packet Data Network Gateways.

- **Severity:** Medium 5.8 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L`)
- **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-x5fh-wf9q-7rgc

## What is CVE-2018-0256?

CVE-2018-0256 is a medium-severity denial of service vulnerability in Cisco Packet Data Network Gateway, 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 peer-to-peer message processing functionality of Cisco Packet Data Network Gateway could allow an unauthenticated, remote attacker to cause the Session Manager (SESSMGR) process on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect validation of peer-to-peer packet headers. An attacker could exploit this vulnerability by sending a crafted peer-to-peer packet through an affected device. A successful exploit could allow the attacker to cause the SESSMGR process on the affected device to restart unexpectedly, which could briefly impact traffic while the SESSMGR process restarts and result in a DoS condition. Cisco Bug IDs: CSCvg88786.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2018-0256?

It affects 1 product.


Products: Cisco Asr 5000 Series Software.

## How do I fix CVE-2018-0256?

No fix has been published for CVE-2018-0256 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-0256 being exploited?

There is no known exploitation of CVE-2018-0256 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Packet Data Network Gateway

- [CVE-2017-3819](https://insights.sbomify.com/CVE-2017-3819/): Privilege escalation in Cisco StarOS (high 8.8)
- [CVE-2017-6612](https://insights.sbomify.com/CVE-2017-6612/): Open redirect in Cisco ASR 5000 Series Aggregation Services Routers (high 8.6)
- [CVE-2017-6672](https://insights.sbomify.com/CVE-2017-6672/): Security feature bypass in Cisco ASR 5000 Series Aggregation Services Routers (high 7.5)
- [CVE-2016-6467](https://insights.sbomify.com/CVE-2016-6467/): Denial of service in Cisco Aggregation Services Router (ASR) 5000 Series Switch (high 7.5)
- [CVE-2016-9203](https://insights.sbomify.com/CVE-2016-9203/): Denial of service in Cisco ASR 5000 (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-0256 and fix it if it is affected.

What it is: CVE-2018-0256 is a medium-severity denial of service vulnerability in Cisco Packet Data Network Gateway, 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-2018-0256 in the wild and no public exploit code.

Affected product: Cisco Packet Data Network Gateway. 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-2018-0256/ (Markdown: https://insights.sbomify.com/CVE-2018-0256/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-0256
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-0256
- OSV: https://osv.dev/vulnerability/CVE-2018-0256

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From sbomify Insights: https://insights.sbomify.com/CVE-2018-0256/
Summaries are generated and may contain mistakes; the official description above is the record.