# CVE-2021-1593: Cisco Packet Tracer for Windows DLL Injection Vulnerability

> Local attackers can inject malicious DLLs via path handling flaws to execute arbitrary code with elevated privileges in Cisco Packet Tracer.

- **Severity:** High 7.3 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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:** A user has to click or open something
- **Fix available:** No
- **Published:** 4 Aug 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-hrcm-7659-jp84

## What is CVE-2021-1593?

CVE-2021-1593 is a high-severity code injection vulnerability in Cisco Packet Tracer, published on 4 Aug 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

A vulnerability in Cisco Packet Tracer for Windows could allow an authenticated, local attacker to perform a DLL injection attack on an affected device. To exploit this vulnerability, the attacker must have valid credentials on the Windows system. This vulnerability is due to incorrect handling of directory paths at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path on the system, which can cause a malicious DLL file to be loaded when the application starts. A successful exploit could allow an attacker with normal user privileges to execute arbitrary code on the affected system with the privileges of another user’s account.

Weakness: CWE-427 (Uncontrolled Search Path Element)

## Which versions are affected by CVE-2021-1593?

It affects 1 product.


Products: Cisco Packet Tracer.

## How do I fix CVE-2021-1593?

No fix has been published for CVE-2021-1593 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1593 being exploited?

There is no known exploitation of CVE-2021-1593 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Packet Tracer

- [CVE-2010-3135](https://insights.sbomify.com/CVE-2010-3135/): Path traversal in n/a (critical 9.3)
- [CVE-2017-12313](https://insights.sbomify.com/CVE-2017-12313/): Path traversal in Cisco Network Academy Packet Tracer (medium 6.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1593 and fix it if it is affected.

What it is: CVE-2021-1593 is a high-severity code injection vulnerability in Cisco Packet Tracer, published on 4 Aug 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-1593 in the wild and no public exploit code.

Affected product: Cisco Packet Tracer. 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-2021-1593/ (Markdown: https://insights.sbomify.com/CVE-2021-1593/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1593
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1593
- OSV: https://osv.dev/vulnerability/CVE-2021-1593

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1593/
Summaries are generated and may contain mistakes; the official description above is the record.