# CVE-2016-6432: Memory corruption in Cisco ASA Software before 9.6(2.1)

> Remote attackers can execute arbitrary code or cause a system reload via crafted NetBIOS packets exploiting a buffer overflow in Cisco ASA Identity Firewall.

- **Severity:** High 8.1 (`CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 Oct 2016
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-x6rr-372c-rmr2

## What is CVE-2016-6432?

CVE-2016-6432 is a high-severity memory corruption vulnerability in Cisco Adaptive Security Appliance Software, published on 27 Oct 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the Identity Firewall feature of Cisco ASA Software before 9.6(2.1) could allow an unauthenticated, remote attacker to cause a reload of the affected system or to remotely execute code. The vulnerability is due to a buffer overflow in the affected code area. An attacker could exploit this vulnerability by sending a crafted NetBIOS packet in response to a NetBIOS probe sent by the ASA software. An exploit could allow the attacker to execute arbitrary code and obtain full control of the system or cause a reload of the affected system. Note: Only traffic directed to the affected system can be used to exploit this vulnerability. This vulnerability affects systems configured in routed and transparent firewall mode and in single or multiple context mode. This vulnerability can be triggered by IPv4 traffic.

Weakness: CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2016-6432?

It affects 1 product.


Products: Cisco Adaptive Security Appliance Software.

## How do I fix CVE-2016-6432?

No fix has been published for CVE-2016-6432 yet. Limit exposure of the affected software until one is available.

## Is CVE-2016-6432 being exploited?

There is no known exploitation of CVE-2016-6432 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Adaptive Security Appliance Software

- [CVE-2025-20333](https://insights.sbomify.com/CVE-2025-20333/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow (critical 9.9, exploited in the wild)
- [CVE-2016-6366](https://insights.sbomify.com/CVE-2016-6366/): Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2026-20349](https://insights.sbomify.com/CVE-2026-20349/): Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection (high 8.6, exploited in the wild)
- [CVE-2024-20353](https://insights.sbomify.com/CVE-2024-20353/): Cisco ASA and FTD Denial of Service (high 8.6, exploited in the wild)
- [CVE-2016-6367](https://insights.sbomify.com/CVE-2016-6367/): Cisco Adaptive Security Appliance (ASA) CLI Remote Code Execution (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-6432 and fix it if it is affected.

What it is: CVE-2016-6432 is a high-severity memory corruption vulnerability in Cisco Adaptive Security Appliance Software, published on 27 Oct 2016. 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-2016-6432 in the wild and no public exploit code.

Affected product: Cisco Adaptive Security Appliance Software. 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-2016-6432/ (Markdown: https://insights.sbomify.com/CVE-2016-6432/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-6432
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-6432
- OSV: https://osv.dev/vulnerability/CVE-2016-6432

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From sbomify Insights: https://insights.sbomify.com/CVE-2016-6432/
Summaries are generated and may contain mistakes; the official description above is the record.