# CVE-2019-1690: Cisco Application Policy Infrastructure Controller IPv6 Link-Local Address Vulnerability

> An unauthenticated adjacent attacker can bypass access controls on Cisco APIC management interfaces via IPv6 link-local addresses.

- **Severity:** Medium 4.3 (`CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Mar 2019
- **Updated:** 21 Nov 2024
- **Also known as:** GHSA-fpjm-2jxg-3phg

## What is CVE-2019-1690?

CVE-2019-1690 is a medium-severity authentication bypass vulnerability in Cisco Application Policy Infrastructure Controller (APIC), published on 11 Mar 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the management interface of Cisco Application Policy Infrastructure Controller (APIC) software could allow an unauthenticated, adjacent attacker to gain unauthorized access on an affected device. The vulnerability is due to a lack of proper access control mechanisms for IPv6 link-local connectivity imposed on the management interface of an affected device. An attacker on the same physical network could exploit this vulnerability by attempting to connect to the IPv6 link-local address on the affected device. A successful exploit could allow the attacker to bypass default access control restrictions on an affected device. Cisco Application Policy Infrastructure Controller (APIC) devices running versions prior to 4.2(0.21c) are affected.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2019-1690?

It affects 1 product.


Products: Cisco Application Policy Infrastructure Controller.

## How do I fix CVE-2019-1690?

No fix has been published for CVE-2019-1690 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-1690 being exploited?

There is no known exploitation of CVE-2019-1690 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Application Policy Infrastructure Controller (APIC)

- [CVE-2021-1393](https://insights.sbomify.com/CVE-2021-1393/): Cisco Application Services Engine Unauthorized Access Vulnerabilities (critical 9.8)
- [CVE-2021-1396](https://insights.sbomify.com/CVE-2021-1396/): Cisco Application Services Engine Unauthorized Access Vulnerabilities (critical 9.8)
- [CVE-2021-1577](https://insights.sbomify.com/CVE-2021-1577/): Cisco Application Policy Infrastructure Controller Arbitrary File Read and Write Vulnerability (critical 9.1)
- [CVE-2023-20011](https://insights.sbomify.com/CVE-2023-20011/): Cross-site request forgery in Cisco Application Policy Infrastructure Controller (APIC) (high 8.8)
- [CVE-2021-1578](https://insights.sbomify.com/CVE-2021-1578/): Cisco Application Policy Infrastructure Controller Privilege Escalation Vulnerability (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-1690 and fix it if it is affected.

What it is: CVE-2019-1690 is a medium-severity authentication bypass vulnerability in Cisco Application Policy Infrastructure Controller (APIC), published on 11 Mar 2019. 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-2019-1690 in the wild and no public exploit code.

Affected product: Cisco Application Policy Infrastructure Controller (APIC). 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-2019-1690/ (Markdown: https://insights.sbomify.com/CVE-2019-1690/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1690
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1690
- OSV: https://osv.dev/vulnerability/CVE-2019-1690

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From sbomify Insights: https://insights.sbomify.com/CVE-2019-1690/
Summaries are generated and may contain mistakes; the official description above is the record.