Vulnerability Database

328,409

Total vulnerabilities in the database

CVE-2020-3161

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.

  • Published: Apr 15, 2020
  • Updated: Nov 4, 2025
  • CVE: CVE-2020-3161
  • Severity: Critical
  • Exploit:

CVSS v3:

  • Severity: Critical
  • Score: 9.8
  • AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2:

  • Severity: High
  • Score: 10
  • AV:N/AC:L/Au:N/C:C/I:C/A:C

CWEs:

Software From Fixed in
cisco / ip_phone_8865_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8865_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8865_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_8851_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8851_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8851_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_7841_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_7821_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8811_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8811_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8811_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_8861_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8861_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8861_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_8845_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8845_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8845_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_7861_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8841_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8841_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8841_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_7811_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8821_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8821_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8821_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / ip_phone_8821-ex_firmware 10.3(1)es14 10.3(1)es14.x
cisco / ip_phone_8821-ex_firmware 11.0(1) 11.0(1).x
cisco / ip_phone_8821-ex_firmware 11.0(5)sr1 11.0(5)sr1.x
cisco / 8831_firmware 10.3(1)es14 10.3(1)es14.x
cisco / 8831_firmware 11.0(1) 11.0(1).x
cisco / 8831_firmware 11.0(5)sr1 11.0(5)sr1.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.