# CVE-2021-1612: Cisco IOS XE SD-WAN Software Arbitrary File Overwrite Vulnerability

> An authenticated local attacker can overwrite arbitrary files on Cisco IOS XE SD-WAN devices via symbolic link manipulation.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N`)
- **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:** 23 Sep 2021
- **Updated:** 7 Nov 2024
- **Also known as:** GHSA-hpj4-vj9f-q9hf

## What is CVE-2021-1612?

CVE-2021-1612 is a medium-severity path traversal vulnerability in Cisco IOS XE SD-WAN Software, published on 23 Sep 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability in the Cisco IOS XE SD-WAN Software CLI could allow an authenticated, local attacker to overwrite arbitrary files on the local system. This vulnerability is due to improper access controls on files within the local file system. An attacker could exploit this vulnerability by placing a symbolic link in a specific location on the local file system. A successful exploit could allow the attacker to overwrite arbitrary files on an affected device.

Weakness: CWE-59 (Improper Link Resolution Before File Access), CWE-61 (UNIX Symbolic Link (Symlink) Following)

## Which versions are affected by CVE-2021-1612?

It affects 1 product.


Products: Cisco Sd-Wan.

## How do I fix CVE-2021-1612?

No fix has been published for CVE-2021-1612 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1612 being exploited?

There is no known exploitation of CVE-2021-1612 in the wild and no public exploit code.

## Other vulnerabilities in Cisco IOS XE SD-WAN Software

- [CVE-2020-3374](https://insights.sbomify.com/CVE-2020-3374/): Cisco SD-WAN vManage Software Authorization Bypass Vulnerability (critical 9.9)
- [CVE-2018-15387](https://insights.sbomify.com/CVE-2018-15387/): Cisco SD-WAN Solution Certificate Validation Bypass Vulnerability (critical 9.8)
- [CVE-2019-1624](https://insights.sbomify.com/CVE-2019-1624/): Cisco SD-WAN Solution Command Injection Vulnerability (high 8.8)
- [CVE-2019-1650](https://insights.sbomify.com/CVE-2019-1650/): Cisco SD-WAN Solution Arbitrary File Overwrite Vulnerability (high 8.8)
- [CVE-2020-3180](https://insights.sbomify.com/CVE-2020-3180/): Cisco SD-WAN Solution Software Static Credentials Vulnerability (high 8.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1612 and fix it if it is affected.

What it is: CVE-2021-1612 is a medium-severity path traversal vulnerability in Cisco IOS XE SD-WAN Software, published on 23 Sep 2021. 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-2021-1612 in the wild and no public exploit code.

Affected product: Cisco IOS XE SD-WAN Software. 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-2021-1612/ (Markdown: https://insights.sbomify.com/CVE-2021-1612/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1612
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1612
- OSV: https://osv.dev/vulnerability/CVE-2021-1612

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1612/
Summaries are generated and may contain mistakes; the official description above is the record.