# CVE-2020-3161: Cisco IP Phones Web Server Remote Code Execution and Denial of Service Vulnerability

> CVE-2020-3161: Cisco IP Phones Web Server Remote Code Execution and Denial of Service Vulnerability. CVSS 9.8 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2020-3161
Last updated: 2025-10-21T23:35:45Z

- Published: 2020-04-15 20:10 UTC · Updated: 2025-10-21 23:35 UTC · Assigner: cisco
- CVSS: 9.8 (CVSS 3.1) · Severity: Critical · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS: 83.9%, 100th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2021-11-03, federal due date 2022-05-03, ransomware use: Unknown
- CWE: CWE-20

## Description

A vulnerability in the web server for Cisco IP Phones could allow an unauthenticated, remote attacker to execute code with root privileges or cause a reload of an affected IP phone, resulting in a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web server of a targeted device. A successful exploit could allow the attacker to remotely execute code with root privileges or cause a reload of an affected IP phone, resulting in a DoS condition.

## CISA required action

Apply updates per vendor instructions.

## Affected vendors and products

- Cisco: Cisco IP phone

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2020-3161)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2020-3161)
- [http://packetstormsecurity.com/files/157265/Cisco-IP-Phone-11.7-Denial-Of-Service.html](http://packetstormsecurity.com/files/157265/Cisco-IP-Phone-11.7-Denial-Of-Service.html)
- [https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voip-phones-rce-dos-rB6EeRXs](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voip-phones-rce-dos-rB6EeRXs)

---

_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


---
Canonical: https://rewindex.com/cve/CVE-2020-3161 · Markdown: https://rewindex.com/cve/CVE-2020-3161.md · JSON: https://rewindex.com/api/v1/cves/CVE-2020-3161 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:47:37.778Z