CVE-2026-121261 in ShapeFile
Summary
by MITRE • 11/03/2026
A vulnerability has been found in phpMyAdmin ShapeFile up to 4.0.1. Impacted is the function ShapeRecord::loadFromFile of the component SHP File Handler. Such manipulation leads to infinite loop. The attack can be executed remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified within phpMyAdmin versions up to 4.0.1 specifically targets the ShapeFile component, which is utilized for handling Geographic Information System data formats such as ESRI Shapefiles. The core technical flaw resides in the ShapeRecord::loadFromFile function, where improper validation of input file structures allows an attacker to craft a maliciously formatted SHP file that triggers an infinite loop condition during parsing operations. This defect represents a classic denial-of-service scenario arising from inadequate boundary checks and state management within the file processing logic, allowing external actors to disrupt service availability by consuming system resources indefinitely without requiring authentication or triggering arbitrary code execution.
From a technical perspective, this issue aligns with CWE-835, which describes loops that never terminate due to missing exit conditions or incorrect loop control variables. In the context of web applications and database management tools like phpMyAdmin, such vulnerabilities are particularly dangerous because they can be triggered remotely via HTTP requests if the application exposes functionality for importing shapefile data. The absence of proper input sanitization means that a specially crafted file uploaded through any interface accepting SHP imports will cause the server-side process to hang indefinitely. This behavior effectively exhausts CPU cycles and memory resources associated with the web server or PHP interpreter, leading to service degradation for all users accessing the platform rather than just the attacker who initiated the request.
The operational impact of this vulnerability is significant in environments where phpMyAdmin is used as a primary interface for database administration involving geospatial data. Since the exploit has been disclosed publicly and proof-of-concept code may be available, automated scanning tools and malicious actors can easily identify vulnerable instances on the internet. The fact that the vendor did not respond to early disclosure attempts suggests a lack of active maintenance or security oversight in this specific version line, leaving users exposed for an extended period. Remote execution capability means no local access is required, lowering the barrier to entry for attackers seeking to cause disruption through denial-of-service attacks against critical infrastructure relying on these tools.
Mitigation strategies must prioritize immediate remediation given the public availability of exploits and the lack of vendor patches. Administrators should upgrade phpMyAdmin to a version where this issue has been resolved by the community or downstream distributors, as upstream development may have stalled for older branches. If upgrading is not immediately feasible, implementing strict input validation at the web server level can help mitigate risk; specifically, configuring reverse proxies like Nginx or Apache to limit request body sizes and timeout durations can prevent long-running processes from consuming excessive resources. Additionally, disabling any unnecessary file upload features related to shapefile handling reduces the attack surface significantly. Security teams should also monitor for unusual spikes in CPU usage associated with PHP worker processes as an indicator of potential exploitation attempts targeting this specific flaw.
This vulnerability underscores the importance of maintaining up-to-date software components and engaging actively with security communities when vendor support is absent. It serves as a reminder that even specialized libraries within widely used applications can introduce critical availability risks if not properly secured against malformed inputs. Adhering to secure coding practices such as those outlined in OWASP guidelines for input validation and resource management would have prevented this infinite loop condition. Organizations should conduct regular vulnerability assessments focusing on third-party components integrated into their web application stacks, ensuring that known issues like CWE-835 are addressed before they can be leveraged by adversaries seeking to disrupt operational continuity through denial-of-service tactics.