# CVE-2006-1651: Security feature bypass in n/a

> Remote attackers may bypass ICMP and TCP filtering rules in Microsoft ISA Server 2004 using IPv6 packets, though this claim is disputed.

- **Severity:** High 7.5 (`AV:N/AC:L/Au:N/C:P/I:P/A:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 6 Apr 2006
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-2988-2x63-c565

## What is CVE-2006-1651?

CVE-2006-1651 is a high-severity vulnerability in n/a, published on 6 Apr 2006. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Microsoft ISA Server 2004 allows remote attackers to bypass certain filtering rules, including ones for (1) ICMP and (2) TCP, via IPv6 packets.  NOTE: An established researcher has disputed this issue, saying that "Neither ISA Server 2004 nor Windows 2003 Basic Firewall support IPv6 filtering ... This is different network protocol.

## Which versions are affected by CVE-2006-1651?

It affects 1 product.


Products: Microsoft Isa Server.

## How do I fix CVE-2006-1651?

No fix has been published for CVE-2006-1651 yet. Limit exposure of the affected software until one is available.

## Is CVE-2006-1651 being exploited?

There is no known exploitation of CVE-2006-1651 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2006-7027](https://insights.sbomify.com/CVE-2006-7027/): Microsoft Internet Security and Acceleration (ISA) Server 2004 logs unusual ASCII characters in the Host header, including the tab, which al (critical 10.0)
- [CVE-2009-0562](https://insights.sbomify.com/CVE-2009-0562/): Memory corruption in n/a (critical 9.3)
- [CVE-2009-1534](https://insights.sbomify.com/CVE-2009-1534/): Memory corruption in n/a (critical 9.3)
- [CVE-2009-1136](https://insights.sbomify.com/CVE-2009-1136/): Code injection in n/a (critical 9.3)
- [CVE-2009-1135](https://insights.sbomify.com/CVE-2009-1135/): Auth bypass in n/a (critical 9.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2006-1651 and fix it if it is affected.

What it is: CVE-2006-1651 is a high-severity vulnerability in n/a, published on 6 Apr 2006. 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-2006-1651 in the wild and no public exploit code.

Affected product: n/a. 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-2006-1651/ (Markdown: https://insights.sbomify.com/CVE-2006-1651/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2006-1651
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2006-1651
- OSV: https://osv.dev/vulnerability/CVE-2006-1651

---
From sbomify Insights: https://insights.sbomify.com/CVE-2006-1651/
Summaries are generated and may contain mistakes; the official description above is the record.