CVE-2018-25246: Wikipedia 12.0 DoS Vulnerability

CVE-2018-25246 Overview

CVE-2018-25246 is a denial of service vulnerability affecting the Wikipedia application version 12.0. The vulnerability allows unauthenticated attackers to crash the application by submitting oversized input through the search functionality. By pasting a large buffer of repeated characters into the search bar, an attacker can trigger an application crash, resulting in service disruption for users.

Critical Impact

Unauthenticated remote attackers can cause a complete application crash through trivial exploitation, resulting in denial of service for all users of the affected Wikipedia application.

Affected Products

• Wikipedia version 12.0 (Microsoft Store application)

Discovery Timeline

• 2026-04-04 - CVE-2018-25246 published to NVD
• 2026-04-07 - Last updated in NVD database

Technical Details for CVE-2018-25246

Vulnerability Analysis

This denial of service vulnerability stems from improper input validation in the search functionality of the Wikipedia 12.0 application. The application fails to properly validate or limit the size of user-supplied input in the search field before processing it. When an attacker submits an excessively large string of repeated characters, the application cannot handle the oversized buffer, leading to resource exhaustion and ultimately an application crash.

The vulnerability is classified under CWE-306, indicating missing authentication for a critical function. In this context, the search functionality lacks proper controls to prevent abuse from unauthenticated users, allowing anyone to trigger the denial of service condition without requiring any form of authentication or authorization.

Root Cause

The root cause of this vulnerability is the absence of input length validation and rate limiting on the search functionality. The application accepts and attempts to process arbitrarily large input strings without enforcing reasonable size constraints. This design flaw allows attackers to overwhelm the application's memory or processing capabilities by submitting malformed input that exceeds expected boundaries.

Attack Vector

The attack vector for CVE-2018-25246 is network-based and requires no authentication or user interaction. An attacker can exploit this vulnerability by:

1. Navigating to the search functionality within the Wikipedia application
2. Pasting or submitting a large buffer of repeated characters into the search input field
3. Triggering the search operation to cause the application to crash

The simplicity of this attack makes it easily reproducible and requires no special tools or technical expertise. Technical details regarding the exploitation technique can be found in the Exploit-DB #45324 entry.

Detection Methods for CVE-2018-25246

Indicators of Compromise

• Repeated application crashes or unexpected terminations of the Wikipedia application
• Abnormally large search queries in application logs exceeding typical user input sizes
• Memory exhaustion events or resource consumption spikes preceding application failures

Detection Strategies

• Monitor application logs for search requests containing unusually large input payloads
• Implement application performance monitoring to detect abnormal memory usage patterns
• Configure crash reporting to alert on repeated application terminations

Monitoring Recommendations

• Enable verbose logging on the Wikipedia application to capture search query details
• Set up automated alerting for application crash events and service interruptions
• Review application logs periodically for patterns indicative of exploitation attempts

How to Mitigate CVE-2018-25246

Immediate Actions Required

• Update the Wikipedia application to a patched version if available from the Microsoft Store
• Consider temporarily disabling or restricting access to the search functionality if exploitation is detected
• Implement input validation at the network perimeter to reject oversized requests

Patch Information

Users should check the Microsoft Store Wikipedia App page for updated versions that address this vulnerability. Ensure automatic updates are enabled to receive the latest security fixes.

Workarounds

• Implement input length restrictions at the application or network level to prevent oversized search queries
• Deploy a web application firewall (WAF) rule to block requests with abnormally large input parameters
• Consider rate limiting on the search endpoint to reduce the impact of repeated exploitation attempts

If direct patching is not immediately possible, organizations should implement network-level controls to validate and limit input sizes before they reach the vulnerable application.