Security

What is Insufficient Verification of Data (CWE-345)?

Learn how insufficient verification of data authenticity works, real-world examples, and how to fix it. Includes code samples and framework-specific fixes...

SP
Shreya Pillai July 29, 2026 5 min read Security
AI-friendly summary

What it is: Insufficient Verification of Data Authenticity (CWE-345) is a vulnerability where a product fails to verify the origin or authenticity of data, leading to acceptance of invalid data.

Why it matters: This can cause unexpected application states and compromise integrity, potentially allowing attackers to manipulate system behavior.

How to fix it: Implement robust validation mechanisms to verify all incoming data before processing.

TL;DR: Insufficient Verification of Data Authenticity (CWE-345) is a vulnerability where systems fail to validate the origin and authenticity of data, leading to potential security risks.

Field Value
CWE ID CWE-345
OWASP Category A08:2025 - Software or Data Integrity Failures
CAPEC CAPEC-111, CAPEC-141, CAPEC-142, CAPEC-148, CAPEC-218, CAPEC-384, CAPEC-385, CAPEC-386, CAPEC-387, CAPEC-388, CAPEC-665, CAPEC-701
Typical Severity High
Affected Technologies web applications, web servers, databases
Detection Difficulty Moderate
Last Updated 2026-07-29

What is Insufficient Verification of Data Authenticity?

Insufficient Verification of Data Authenticity (CWE-345) is a type of vulnerability where the product does not sufficiently verify the origin or authenticity of data, causing it to accept invalid data. As defined by the MITRE Corporation under CWE-345, and classified by the OWASP Foundation under A08:2025 - Software or Data Integrity Failures.

Quick Summary

Insufficient Verification of Data Authenticity is a critical vulnerability where systems fail to validate the origin and authenticity of data. This can lead to unexpected application states and compromise integrity, potentially allowing attackers to manipulate system behavior. Jump to: Overview · How It Works · Business Impact · Attack Scenario · Detection · Fixes · Framework-Specific Fixes · AI Prompt · Best Practices · FAQ · Related Vulnerabilities

Jump to: Quick Summary · Insufficient Verification of Data Authenticity Overview · How Insufficient Verification of Data Authenticity Works · Business Impact of Insufficient Verification of Data Authenticity · Insufficient Verification of Data Authenticity Attack Scenario · How to Detect Insufficient Verification of Data Authenticity · How to Fix Insufficient Verification of Data Authenticity · Framework-Specific Fixes for Insufficient Verification of Data Authenticity · How to Ask AI to Check Your Code for Insufficient Verification of Data Authenticity · Insufficient Verification of Data Authenticity Best Practices Checklist · Insufficient Verification of Data Authenticity FAQ · Vulnerabilities Related to Insufficient Verification of Data Authenticity · References · Scan Your Own Site

Insufficient Verification of Data Authenticity Overview

What

Insufficient Verification of Data Authenticity is a vulnerability where systems fail to validate the origin and authenticity of data, leading to potential security risks.

Why it matters

This weakness can cause unexpected application states and compromise integrity, potentially allowing attackers to manipulate system behavior.

Where it occurs

It commonly affects web applications, web servers, and databases that process untrusted inputs without proper validation or authentication checks.

Who is affected

Developers and administrators of systems that do not properly verify data authenticity are at risk.

Who is NOT affected

Systems already using robust mechanisms to validate the origin and integrity of incoming data are less likely to be vulnerable.

How Insufficient Verification of Data Authenticity Works

Root Cause

The root cause lies in inadequate validation or verification of data origins, leading to acceptance of invalid or malicious inputs.

Attack Flow

  1. An attacker injects unverified data into the system.
  2. The system processes this data without proper checks.
  3. This leads to unexpected states and potential integrity compromises.

Prerequisites to Exploit

  • External input must be accepted and processed by the system.
  • No validation or authentication mechanisms are in place for incoming data.

Vulnerable Code

def process_data(input):
    # Process unverified data directly
    return input

This code accepts external input without any verification, making it vulnerable to manipulation.

Secure Code

def validate_and_process_data(input):
    if not verify_origin(input):
        raise ValueError("Invalid origin")
    return input

The secure version verifies the origin of the data before processing it.

Business Impact of Insufficient Verification of Data Authenticity

Integrity

  • Compromised integrity can lead to unexpected application states and potential data manipulation.

Financial, compliance, and reputation impacts may follow from these technical issues.

Insufficient Verification of Data Authenticity Attack Scenario

  1. An attacker injects malicious data into a system.
  2. The system processes this unverified data.
  3. This leads to an unexpected state or integrity compromise.

How to Detect Insufficient Verification of Data Authenticity

Manual Testing

  • [ ] Review code for direct acceptance of external input without validation.
  • [ ] Check if there are any mechanisms in place to verify the origin and authenticity of data.

Automated Scanners (SAST/DAST)

Static analysis can identify unverified inputs, while dynamic testing simulates attacks on the system.

PenScan Detection

PenScan’s scanner engines like ZAP, Nuclei, Wapiti, Nikto, SSLyze, Dalfox, and Nmap can detect this vulnerability.

False Positive Guidance

A false positive occurs if a pattern looks risky but is actually safe due to context that the scanner cannot determine.

How to Fix Insufficient Verification of Data Authenticity

  • Implement robust validation mechanisms.
  • Verify data origins before processing.

Framework-Specific Fixes for Insufficient Verification of Data Authenticity

Python/Django

def validate_and_process_data(input):
    if not verify_origin(input):
        raise ValueError("Invalid origin")
    return input

Java

public void processData(String input) {
    if (!verifyOrigin(input)) {
        throw new IllegalArgumentException("Invalid origin");
    }
}

How to Ask AI to Check Your Code for Insufficient Verification of Data Authenticity

Copy-paste prompt

Review the following Python code block for potential CWE-345 Insufficient Verification of Data Authenticity vulnerabilities and rewrite it using robust validation mechanisms: [paste code here]

Insufficient Verification of Data Authenticity Best Practices Checklist

✅ Implement rigorous data origin verification. ✅ Use secure protocols to validate incoming data. ✅ Regularly audit systems for unverified data inputs.

Insufficient Verification of Data Authenticity FAQ

How does insufficient verification of data authenticity work?

It occurs when a system fails to verify the origin or integrity of incoming data, leading to acceptance of potentially malicious information.

What are the common consequences of insufficient verification of data authenticity?

This weakness can lead to unexpected states and compromise data integrity within an application.

How do attackers exploit insufficient verification of data authenticity?

Attackers inject or manipulate unverified data, causing systems to process invalid or malicious information.

What are the prerequisites for exploiting insufficient verification of data authenticity?

The system must accept and process external input without proper validation or authentication checks.

How can I detect insufficient verification of data authenticity in my code?

Use static analysis tools to identify unverified data inputs, and manually review how data is processed and validated.

What are the best practices for preventing insufficient verification of data authenticity?

Implement robust validation mechanisms to verify all incoming data before processing it.

How can I fix existing instances of insufficient verification of data authenticity in my application?

Add checks to validate the origin and integrity of data before accepting or using it.

CWE Name Relationship
CWE-693 Protection Mechanism Failure (ChildOf)  

References

Scan Your Own Site

Manual code review catches what you know to look for. An automated scan catches what you didn’t. Scan your own website using PenScan to find Insufficient Verification of Data Authenticity and other risks before an attacker does.