CVE-2026-23801 in The Issue Plugin
Summary
by MITRE • 03/05/2026
Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in fuelthemes The Issue theissue allows PHP Local File Inclusion.This issue affects The Issue: from n/a through <= 1.6.11.
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Analysis
by VulDB Data Team • 03/11/2026
The vulnerability CVE-2026-23801 represents a critical PHP Remote File Inclusion flaw in the fuelthemes The Issue application, specifically impacting versions through 1.6.11. This vulnerability stems from improper control of filename parameters in include/require statements, creating an avenue for attackers to manipulate file inclusion mechanisms. The flaw allows adversaries to execute arbitrary code by injecting malicious file paths into the application's include functions, effectively bypassing intended security boundaries and potentially gaining unauthorized access to the system.
This vulnerability directly maps to CWE-88, which describes improper control of filename for inclusion or import statements, and aligns with ATT&CK technique T1190 for exploitation of remote file inclusion vulnerabilities. The issue manifests when the application fails to properly validate or sanitize user-supplied input that is subsequently used in PHP include/require statements. Attackers can exploit this weakness by crafting malicious payloads that reference remote files or local system paths, enabling them to execute arbitrary PHP code on the target server. The vulnerability's impact is particularly severe because it allows for local file inclusion attacks that can escalate privileges and potentially lead to complete system compromise.
The operational impact of this vulnerability extends beyond simple code execution, as it can enable attackers to access sensitive system files, manipulate database connections, and potentially establish persistent backdoors within the affected environment. When exploited successfully, the vulnerability can result in data breaches, system infiltration, and unauthorized access to administrative functions. Organizations running affected versions of fuelthemes The Issue face significant risk of compromise, particularly if the application has write permissions or if the server configuration allows remote file inclusion. The vulnerability's exploitation typically requires minimal prerequisites and can be automated through various attack frameworks, making it particularly dangerous in environments with inadequate input validation or security controls.
Mitigation strategies for CVE-2026-23801 should prioritize immediate remediation through version updates to the latest stable release of fuelthemes The Issue. Organizations must implement strict input validation and sanitization measures, particularly for any parameters used in include/require statements, ensuring that all user-supplied data undergoes rigorous validation before processing. The implementation of PHP's open_basedir directive and disabling of remote file inclusion features through configuration settings can provide additional protective layers. Security measures should also include monitoring for suspicious file inclusion patterns, implementing web application firewalls to detect and block malicious requests, and conducting comprehensive security assessments to identify potential exploitation vectors. Regular security updates, proper access controls, and network segmentation can further reduce the attack surface and limit the potential impact of successful exploitation attempts.