# CVE-2007-3843: Security feature bypass in n/a

> Remote attackers can bypass CIFS security signatures by exploiting a kernel variable check error, allowing traffic spoofing when signing is configured.

- **Severity:** Medium 4.3 (`AV:N/AC:M/Au:N/C:N/I:P/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Aug 2007
- **Updated:** 7 Aug 2024
- **Also known as:** GHSA-xmg2-6455-627q

## What is CVE-2007-3843?

CVE-2007-3843 is a medium-severity vulnerability in Linux kernel, published on 9 Aug 2007. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Linux kernel before 2.6.23-rc1 checks the wrong global variable for the CIFS sec mount option, which might allow remote attackers to spoof CIFS network traffic that the client configured for security signatures, as demonstrated by lack of signing despite sec=ntlmv2i in a SetupAndX request.

## Which versions are affected by CVE-2007-3843?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2007-3843?

Upgrade to a fixed version.

## Is CVE-2007-3843 being exploited?

There is no known exploitation of CVE-2007-3843 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2007-3843 and fix it if it is affected.

What it is: CVE-2007-3843 is a medium-severity vulnerability in Linux kernel, published on 9 Aug 2007. 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-2007-3843 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2007-3843/ (Markdown: https://insights.sbomify.com/CVE-2007-3843/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2007-3843
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2007-3843
- OSV: https://osv.dev/vulnerability/CVE-2007-3843

---
From sbomify Insights: https://insights.sbomify.com/CVE-2007-3843/
Summaries are generated and may contain mistakes; the official description above is the record.