# CVE-2017-6672: Security feature bypass in Cisco ASR 5000 Series Aggregation Services Routers

> Unauthenticated remote attackers can bypass configured Access Control List rules on Cisco ASR 5000 routers due to filtering mechanism flaws.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **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 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-3xgv-53v3-rfw4

## What is CVE-2017-6672?

CVE-2017-6672 is a high-severity vulnerability in Cisco ASR 5000 Series Aggregation Services Routers, published on 25 Jul 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in certain filtering mechanisms of access control lists (ACLs) for Cisco ASR 5000 Series Aggregation Services Routers through 21.x could allow an unauthenticated, remote attacker to bypass ACL rules that have been configured for an affected device. More Information: CSCvb99022 CSCvc16964 CSCvc37351 CSCvc54843 CSCvc63444 CSCvc77815 CSCvc88658 CSCve08955 CSCve14141 CSCve33870.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2017-6672?

It affects 1 product.


Products: Cisco Asr 5000 Series Software.

## How do I fix CVE-2017-6672?

No fix has been published for CVE-2017-6672 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-6672 being exploited?

There is no known exploitation of CVE-2017-6672 in the wild and no public exploit code.

## Other vulnerabilities in Cisco ASR 5000 Series Aggregation Services Routers

- [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-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)
- [CVE-2016-6466](https://insights.sbomify.com/CVE-2016-6466/): Denial of service in Cisco StarOS 20.0.0 through 21.0.M0.64246 (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2017-6672 and fix it if it is affected.

What it is: CVE-2017-6672 is a high-severity vulnerability in Cisco ASR 5000 Series Aggregation Services Routers, published on 25 Jul 2017. 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-2017-6672 in the wild and no public exploit code.

Affected product: Cisco ASR 5000 Series Aggregation Services Routers. 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-2017-6672/ (Markdown: https://insights.sbomify.com/CVE-2017-6672/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-6672
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-6672
- OSV: https://osv.dev/vulnerability/CVE-2017-6672

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-6672/
Summaries are generated and may contain mistakes; the official description above is the record.