# CVE-2018-6851: Privilege escalation in n/a

> Local attackers can escalate privileges to SYSTEM by exploiting an IOCTL vulnerability in Sophos SafeGuard products to modify security descriptors.

- **Severity:** High 7.8 (`CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 9 Jul 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-h637-372j-4mwq

## What is CVE-2018-6851?

CVE-2018-6851 is a high-severity vulnerability in n/a, published on 9 Jul 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Sophos SafeGuard Enterprise before 8.00.5, SafeGuard Easy before 7.00.3, and SafeGuard LAN Crypt before 3.95.2 are vulnerable to Local Privilege Escalation via IOCTL 0x80206040. By crafting an input buffer we can control the execution path to the point where the constant DWORD 0 will be written to a user-controlled address. We can take advantage of this condition to zero-out the pointer to the security descriptor in the object header of a privileged process or modify the security descriptor itself and run code in the context of a process running as SYSTEM.

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

## Which versions are affected by CVE-2018-6851?

It affects 3 products.


Products: Sophos Safeguard Easy Device Encryption Client, Sophos Safeguard Enterprise Client, Sophos Safeguard Lan Crypt Client.

## How do I fix CVE-2018-6851?

No fix has been published for CVE-2018-6851 yet. Limit exposure of the affected software until one is available.

## Is CVE-2018-6851 being exploited?

There is no known exploitation of CVE-2018-6851 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2018-6852](https://insights.sbomify.com/CVE-2018-6852/): Privilege escalation in n/a (high 7.8)
- [CVE-2018-6853](https://insights.sbomify.com/CVE-2018-6853/): Privilege escalation in n/a (high 7.8)
- [CVE-2018-6854](https://insights.sbomify.com/CVE-2018-6854/): Privilege escalation in n/a (high 7.8)
- [CVE-2018-6855](https://insights.sbomify.com/CVE-2018-6855/): Privilege escalation in n/a (high 7.8)
- [CVE-2018-6856](https://insights.sbomify.com/CVE-2018-6856/): Privilege escalation in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-6851 and fix it if it is affected.

What it is: CVE-2018-6851 is a high-severity vulnerability in n/a, published on 9 Jul 2018. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2018-6851 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-2018-6851/ (Markdown: https://insights.sbomify.com/CVE-2018-6851/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-6851
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-6851
- OSV: https://osv.dev/vulnerability/CVE-2018-6851

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-6851/
Summaries are generated and may contain mistakes; the official description above is the record.