CVE-2020-3161

Improper Input Validation in 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

Verified by Precogs Threat Research
Last Updated: Oct 28, 2025
Base Score
9.8CRITICAL

Executive Summary

CVE-2020-3161 is a critical severity vulnerability affecting appsec. It is classified as CWE-20. This vulnerability is actively being exploited in the wild.

Precogs AI Insight

"The web server for Cisco IP Phones improperly validates HTTP requests, leading to memory corruption. Attackers send crafted HTTP packets to execute code with root privileges or brick the device. Precogs Binary SAST natively detects missing boundary validations in embedded web servers."

Exploit Probability (EPSS)
High (87.1%)
Public POC
Available
Exploit Probability
High (84%)
Public POC
Actively Exploited
Affected Assets
appsecCWE-20

What is this vulnerability?

CVE-2020-3161 is categorized as a critical Improper Input Validation flaw with a CVSS base score of 9.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

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.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

MetricValue
CVSS Base Score9.8 (CRITICAL)
Vector StringCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
PublishedApril 15, 2020
Last ModifiedOctober 28, 2025
Related CWEsCWE-20, CWE-20

Impact on Systems

Data Exfiltration: Attackers can extract sensitive data from backend databases, configuration files, or internal services.

Authentication Bypass: Exploiting this flaw may allow unauthorized access to protected resources and administrative interfaces.

Lateral Movement: Once initial access is gained, attackers can pivot to internal systems and escalate privileges.

How to Fix and Mitigate CVE-2020-3161

  1. Apply Vendor Patches Immediately: This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog. Apply updates per vendor instructions.
  2. Verify Patch Deployment: Confirm all instances are updated using Precogs continuous monitoring.
  3. Review Audit Logs: Investigate historical access logs for indicators of compromise related to this attack surface.
  4. Implement Defense-in-Depth: Deploy WAF rules, network segmentation, and endpoint detection to limit blast radius.

Defending with Precogs AI

The web server for Cisco IP Phones improperly validates HTTP requests, leading to memory corruption. Attackers send crafted HTTP packets to execute code with root privileges or brick the device. Precogs Binary SAST natively detects missing boundary validations in embedded web servers.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

StageDetail
SourceUntrusted User Input
VectorInput flows through the application logic without sanitization
SinkExecution or Rendering Sink
ImpactApplication compromise, Logic Bypass, Data Exfiltration

Vulnerable Code Pattern

# ❌ VULNERABLE: Unsanitized Input Flow
def process_request(request):
    user_input = request.GET.get('data')
    # Taint sink: processing untrusted data
    execute_logic(user_input)
    return {"status": "success"}

Secure Code Pattern

# ✅ SECURE: Input Validation & Sanitization
def process_request(request):
    user_input = request.GET.get('data')
    
    # Sanitized boundary check
    if not is_valid_format(user_input):
        raise ValueError("Invalid input format")
        
    sanitized_data = sanitize(user_input)
    execute_logic(sanitized_data)
    return {"status": "success"}

How Precogs Detects This

Precogs AI Analysis Engine maps untrusted input directly to execution sinks to catch complex application security vulnerabilities.\n

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The Appmax plugin for WordPress is vulnerable to Improper Input Validation in all versions up to, and including, 1.

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CWE-20

Is your system affected?

Precogs AI detects CVE-2020-3161 in compiled binaries, LLMs, and application layers — even without source code access.