# CVE-2021-1321: Command injection in Cisco Small Business RV Series Router Firmware

> Authenticated attackers can execute arbitrary code as root or cause a denial of service on Cisco Small Business RV Series Routers via crafted HTTP requests.

- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 Feb 2021
- **Updated:** 8 Nov 2024
- **Also known as:** GHSA-hcxg-m989-4j63

## What is CVE-2021-1321?

CVE-2021-1321 is a high-severity command injection vulnerability in Cisco Small Business RV Series Router Firmware, published on 4 Feb 2021. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly. These vulnerabilities are due to improper validation of user-supplied input in the web-based management interface. An attacker could exploit these vulnerabilities by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system or cause the device to reload, resulting in a denial of service (DoS) condition. To exploit these vulnerabilities, an attacker would need to have valid administrator credentials on the affected device.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2021-1321?

It affects 6 products.


Products: Cisco Rv016 Multi-Wan Vpn Router Firmware, Cisco Rv042 Dual Wan Vpn Router Firmware, Cisco Rv042g Dual Gigabit Wan Vpn Router Firmware, Cisco Rv082 Dual Wan Vpn Router Firmware, Cisco Rv320 Dual Gigabit Wan Vpn Router Firmware, Cisco Rv325 Dual Gigabit Wan Vpn Router Firmware.

## How do I fix CVE-2021-1321?

No fix has been published for CVE-2021-1321 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-1321 being exploited?

There is no known exploitation of CVE-2021-1321 in the wild and no public exploit code.

## Other vulnerabilities in Cisco Small Business RV Series Router Firmware

- [CVE-2021-1314](https://insights.sbomify.com/CVE-2021-1314/): Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities (high 7.2)
- [CVE-2021-1315](https://insights.sbomify.com/CVE-2021-1315/): Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities (high 7.2)
- [CVE-2021-1316](https://insights.sbomify.com/CVE-2021-1316/): Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities (high 7.2)
- [CVE-2021-1317](https://insights.sbomify.com/CVE-2021-1317/): Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities (high 7.2)
- [CVE-2021-1318](https://insights.sbomify.com/CVE-2021-1318/): Cisco Small Business RV Series Routers Management Interface Command Injection Vulnerabilities (high 7.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-1321 and fix it if it is affected.

What it is: CVE-2021-1321 is a high-severity command injection vulnerability in Cisco Small Business RV Series Router Firmware, published on 4 Feb 2021. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-1321 in the wild and no public exploit code.

Affected product: Cisco Small Business RV Series Router Firmware. 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-2021-1321/ (Markdown: https://insights.sbomify.com/CVE-2021-1321/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-1321
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-1321
- OSV: https://osv.dev/vulnerability/CVE-2021-1321

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-1321/
Summaries are generated and may contain mistakes; the official description above is the record.