# CVE-2002-0004: Use after free in n/a

> Local attackers can execute arbitrary code via heap corruption in the at command, potentially escalating privileges.

- **Severity:** High 7.2 (`AV:L/AC:L/Au:N/C:C/I:C/A:C`)
- **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:** 25 Jun 2002
- **Updated:** 8 Aug 2024
- **Also known as:** GHSA-hv62-hp8h-9vjg

## What is CVE-2002-0004?

CVE-2002-0004 is a high-severity use after free vulnerability in Debian Debian Linux, published on 25 Jun 2002. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Heap corruption vulnerability in the "at" program allows local users to execute arbitrary code via a malformed execution time, which causes at to free the same memory twice.

## Which versions are affected by CVE-2002-0004?

It affects 9 products.


Products: Caldera Openlinux Server, Caldera Openlinux Workstation, Debian Debian Linux, Freebsd Freebsd, Mandrakesoft Mandrake Linux, Netbsd Netbsd, Redhat Linux, Slackware Slackware Linux, Suse Suse Linux.

## How do I fix CVE-2002-0004?

No fix has been published for CVE-2002-0004 yet. Limit exposure of the affected software until one is available.

## Is CVE-2002-0004 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2002-0004 exists.

Public exploit code:

- AT 3.1.8 - Formatted Time Heap Overflow (exploitdb)

## Other vulnerabilities in Debian Debian Linux

- [CVE-2001-1030](https://insights.sbomify.com/CVE-2001-1030/): Auth bypass in n/a (high 7.5)
- [CVE-2001-0980](https://insights.sbomify.com/CVE-2001-0980/): Command injection in n/a (high 7.5)
- [CVE-2002-0835](https://insights.sbomify.com/CVE-2002-0835/): Denial of service in n/a (medium 5.0)
- [CVE-2003-0658](https://insights.sbomify.com/CVE-2003-0658/): Path traversal in n/a (medium 5.0)
- [CVE-2002-0512](https://insights.sbomify.com/CVE-2002-0512/): Privilege escalation in n/a (medium 4.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2002-0004 and fix it if it is affected.

What it is: CVE-2002-0004 is a high-severity use after free vulnerability in Debian Debian Linux, published on 25 Jun 2002. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2002-0004 exists.

Affected product: Debian Debian Linux. 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-2002-0004/ (Markdown: https://insights.sbomify.com/CVE-2002-0004/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2002-0004
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2002-0004
- OSV: https://osv.dev/vulnerability/CVE-2002-0004

---
From sbomify Insights: https://insights.sbomify.com/CVE-2002-0004/
Summaries are generated and may contain mistakes; the official description above is the record.