# CVE-2017-6608: Denial of service in Cisco ASA Software

> An unauthenticated remote attacker can cause a system reload by sending crafted SSL or TLS packets to Cisco ASA firewalls.

- **Severity:** High 8.6 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/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:** 20 Apr 2017
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-q2fv-3xmc-j293

## What is CVE-2017-6608?

CVE-2017-6608 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 20 Apr 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A vulnerability in the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) code of Cisco ASA Software could allow an unauthenticated, remote attacker to cause a reload of the affected system. The vulnerability is due to improper parsing of crafted SSL or TLS packets. An attacker could exploit this vulnerability by sending a crafted packet to 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 and IPv6 traffic. A valid SSL or TLS session is needed to exploit this vulnerability. This vulnerability affects Cisco ASA Software running on the following products: Cisco ASA 1000V Cloud Firewall, Cisco ASA 5500 Series Adaptive Security Appliances, Cisco ASA 5500-X Series Next-Generation Firewalls, Cisco ASA Services Module for Cisco Catalyst 6500 Series Switches and Cisco 7600 Series Routers, Cisco Adaptive Security Virtual Appliance (ASAv), Cisco Firepower 9300 ASA Security Module, Cisco ISA 3000 Industrial Security Appliance. Fixed versions: 8.4(7.31) 9.0(4.39) 9.1(7) 9.2(4.6) 9.3(3.8) 9.4(2) 9.5(2). Cisco Bug IDs: CSCuv48243.

Weakness: CWE-399

## Which versions are affected by CVE-2017-6608?

It affects 1 product.


Products: Cisco Adaptive Security Appliance Software.

## How do I fix CVE-2017-6608?

No fix has been published for CVE-2017-6608 yet. Limit exposure of the affected software until one is available.

## Is CVE-2017-6608 being exploited?

There is no known exploitation of CVE-2017-6608 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-2017-6608 and fix it if it is affected.

What it is: CVE-2017-6608 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 20 Apr 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-2017-6608 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-2017-6608/ (Markdown: https://insights.sbomify.com/CVE-2017-6608/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-6608
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-6608
- OSV: https://osv.dev/vulnerability/CVE-2017-6608

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-6608/
Summaries are generated and may contain mistakes; the official description above is the record.