# CVE-2020-7453: Information disclosure in FreeBSD

> A missing null termination check in FreeBSD's jail_set allows a malicious jail superuser to read kernel memory via jail_get.

- **Severity:** Medium 6.0 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Apr 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-329c-g8g4-89hm

## What is CVE-2020-7453?

CVE-2020-7453 is a medium-severity vulnerability in Freebsd Freebsd, published on 28 Apr 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In FreeBSD 12.1-STABLE before r359021, 12.1-RELEASE before 12.1-RELEASE-p3, 11.3-STABLE before r359020, and 11.3-RELEASE before 11.3-RELEASE-p7, a missing null termination check in the jail_set configuration option "osrelease" may return more bytes with a subsequent jail_get system call allowing a malicious jail superuser with permission to create nested jails to read kernel memory.

Weakness: CWE-754 (Improper Check for Unusual or Exceptional Conditions)

## Which versions are affected by CVE-2020-7453?

It affects 1 product.


Products: Freebsd Freebsd.

## How do I fix CVE-2020-7453?

No fix has been published for CVE-2020-7453 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-7453 being exploited?

There is no known exploitation of CVE-2020-7453 in the wild and no public exploit code.

## Other vulnerabilities in Freebsd Freebsd

- [CVE-2018-17160](https://insights.sbomify.com/CVE-2018-17160/): Memory corruption in FreeBSD (critical 10.0)
- [CVE-2014-3954](https://insights.sbomify.com/CVE-2014-3954/): Memory corruption in n/a (critical 10.0)
- [CVE-2006-4304](https://insights.sbomify.com/CVE-2006-4304/): Memory corruption in n/a (critical 10.0)
- [CVE-2006-0226](https://insights.sbomify.com/CVE-2006-0226/): Integer overflow in n/a (critical 10.0)
- [CVE-2004-0002](https://insights.sbomify.com/CVE-2004-0002/): Denial of service in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-7453 and fix it if it is affected.

What it is: CVE-2020-7453 is a medium-severity vulnerability in Freebsd Freebsd, published on 28 Apr 2020. 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-2020-7453 in the wild and no public exploit code.

Affected product: Freebsd Freebsd. 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-2020-7453/ (Markdown: https://insights.sbomify.com/CVE-2020-7453/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-7453
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-7453
- OSV: https://osv.dev/vulnerability/CVE-2020-7453

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-7453/
Summaries are generated and may contain mistakes; the official description above is the record.