CVE-2026-28129 in Little Birdies Plugin
Summary
by MITRE • 03/05/2026
Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in axiomthemes Little Birdies little-birdies allows PHP Local File Inclusion.This issue affects Little Birdies: from n/a through <= 1.3.16.
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Analysis
by VulDB Data Team • 03/07/2026
The vulnerability identified as CVE-2026-28129 represents a critical PHP Remote File Inclusion flaw within the axiomthemes Little Birdies plugin, specifically affecting versions through 1.3.16. This vulnerability resides in the improper control of filename parameters within include/require statements, creating a pathway for attackers to execute arbitrary code on affected systems. The flaw manifests when user-supplied input is directly incorporated into PHP include or require directives without adequate sanitization or validation, allowing malicious actors to manipulate the include path and potentially load remote files or local system files. The vulnerability is classified under CWE-98 as Improper Control of Filename for Include/Require Statement, which is a well-documented weakness in web application security that has been consistently exploited in various PHP applications over the years. The ATT&CK framework categorizes this as a technique under T1190 - Exploit Public-Facing Application, where attackers leverage web application vulnerabilities to gain unauthorized access and execute malicious code. The specific impact occurs when the plugin fails to properly validate or sanitize user input that is used in file inclusion operations, creating a direct attack surface for remote code execution.
The technical exploitation of this vulnerability requires an attacker to manipulate the filename parameter passed to include or require statements within the Little Birdies plugin code. When the plugin processes user input through parameters such as $_GET or $_POST variables and directly incorporates them into file inclusion functions, attackers can inject malicious file paths or URLs. This allows for the inclusion of remote PHP files hosted on attacker-controlled servers, enabling remote code execution capabilities. The vulnerability is particularly dangerous because it operates at the core level of PHP execution, where the include/require statements are processed before the application logic. Attackers can leverage this to include system files, PHP extensions, or malicious payloads that execute with the privileges of the web server. The attack vector typically involves crafting specific URL parameters that, when processed by the vulnerable plugin, result in the inclusion of attacker-controlled files. This creates a persistent threat where attackers can establish backdoors, exfiltrate data, or escalate privileges within the compromised environment.
The operational impact of CVE-2026-28129 extends beyond immediate code execution to encompass broader security implications for affected systems. Organizations running vulnerable versions of the Little Birdies plugin face potential data breaches, system compromise, and unauthorized access to sensitive information. The vulnerability can be exploited by attackers with minimal technical expertise, making it particularly dangerous in environments where multiple WordPress sites are hosted on the same server. Once exploited, attackers can establish persistent access through backdoor files or shell scripts, allowing for ongoing surveillance and control of the compromised systems. The vulnerability also poses risks to network infrastructure, as compromised systems can be used as launch points for further attacks against internal networks. Additionally, the exposure of system files through local file inclusion can reveal sensitive information such as database credentials, configuration files, and user data. The impact is compounded by the fact that this vulnerability affects a widely used WordPress theme, increasing the potential attack surface and making it a prime target for automated scanning and exploitation tools. Organizations may face regulatory compliance issues and reputational damage if successful exploitation leads to data loss or unauthorized access to customer information.
Mitigation strategies for CVE-2026-28129 require immediate action to address the vulnerable plugin version and implement defensive measures. The primary recommendation is to upgrade the Little Birdies plugin to version 1.3.17 or later, which contains the necessary patches to prevent the improper control of filename parameters in include/require statements. System administrators should also implement input validation and sanitization measures to prevent user-supplied data from being directly incorporated into file inclusion operations. This includes implementing proper parameter validation, using allowlists for acceptable file paths, and avoiding dynamic include statements that rely on user input. Additional security measures include restricting file inclusion capabilities through PHP configuration settings, implementing web application firewalls to detect and block malicious requests, and monitoring system logs for suspicious activity related to file inclusion attempts. Organizations should also conduct thorough security assessments of their WordPress installations to identify other potential vulnerabilities and ensure that all plugins and themes are kept up to date with the latest security patches. The implementation of secure coding practices, including the use of static code analysis tools and regular security reviews, can help prevent similar vulnerabilities from being introduced in future development cycles. Furthermore, network segmentation and least privilege access controls should be enforced to limit the potential damage from successful exploitation attempts.