# CVE-2020-3139: Cisco Application Policy Infrastructure Controller Out Of Band Management IP Tables Bypass Vulnerability

> Unauthenticated remote attackers can bypass IP table rules on the Cisco APIC out-of-band management interface, allowing unauthorized access to restricted ports.

- **Severity:** Medium 5.3 (`CVSS:3.0/AV:N/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:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 26 Jan 2020
- **Updated:** 15 Nov 2024
- **Also known as:** GHSA-j72w-hrcq-cmrg

## What is CVE-2020-3139?

CVE-2020-3139 is a medium-severity vulnerability in Cisco Application Policy Infrastructure Controller (APIC), published on 26 Jan 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the out of band (OOB) management interface IP table rule programming for Cisco Application Policy Infrastructure Controller (APIC) could allow an unauthenticated, remote attacker to bypass configured deny entries for specific IP ports. These IP ports would be permitted to the OOB management interface when, in fact, the packets should be dropped. The vulnerability is due to the configuration of specific IP table entries for which there is a programming logic error that results in the IP port being permitted. An attacker could exploit this vulnerability by sending traffic to the OOB management interface on the targeted device. A successful exploit could allow the attacker to bypass configured IP table rules to drop specific IP port traffic. The attacker has no control over the configuration of the device itself. This vulnerability affects Cisco APIC releases prior to the first fixed software Release 4.2(3j).

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2020-3139?

It affects 1 product.


Products: Cisco Application Policy Infrastructure Controller.

## How do I fix CVE-2020-3139?

No fix has been published for CVE-2020-3139 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-3139 being exploited?

There is no known exploitation of CVE-2020-3139 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-2020-3139 and fix it if it is affected.

What it is: CVE-2020-3139 is a medium-severity vulnerability in Cisco Application Policy Infrastructure Controller (APIC), published on 26 Jan 2020. 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-2020-3139 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-2020-3139/ (Markdown: https://insights.sbomify.com/CVE-2020-3139/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-3139
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-3139
- OSV: https://osv.dev/vulnerability/CVE-2020-3139

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-3139/
Summaries are generated and may contain mistakes; the official description above is the record.