CVE-2025-49983 in WPThumb Plugin
Summary
by MITRE • 06/20/2025
Server-Side Request Forgery (SSRF) vulnerability in Joe Hoyle WPThumb allows Server Side Request Forgery. This issue affects WPThumb: from n/a through 0.10.
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Analysis
by VulDB Data Team • 06/20/2025
The CVE-2025-49983 vulnerability represents a critical server-side request forgery flaw within the Joe Hoyle WPThumb WordPress plugin, which poses significant security risks to affected websites. This vulnerability exists in versions ranging from n/a through 0.10, indicating that all versions within this range are potentially compromised. The issue stems from improper input validation and sanitization mechanisms that fail to adequately restrict external requests initiated by the server. Attackers can exploit this weakness to manipulate the plugin's functionality and potentially gain unauthorized access to internal network resources or sensitive data.
The technical implementation of this SSRF vulnerability occurs when the WPThumb plugin processes external image URLs without sufficient validation of the requested resources. This flaw allows malicious actors to craft specially formatted requests that can bypass normal network restrictions and access internal systems that would typically be protected from external access. The vulnerability specifically affects the plugin's image processing capabilities where it fetches remote images and processes them for display on WordPress sites. When users or administrators provide external URLs, the plugin's server-side code fails to properly validate these inputs, creating an attack surface that can be exploited to perform unauthorized requests.
The operational impact of this vulnerability extends beyond simple data theft or unauthorized access. Attackers can leverage this SSRF flaw to perform reconnaissance activities against internal network infrastructure, potentially discovering other vulnerable systems or services that exist behind firewalls. The vulnerability can also enable attackers to exploit other weaknesses within the internal network by using the compromised WordPress server as a pivot point for further attacks. This makes the vulnerability particularly dangerous as it can serve as an entry point for more sophisticated attack vectors. Additionally, the impact affects not only the immediate WordPress installation but potentially entire network infrastructures that rely on the plugin's functionality.
Security mitigations for this vulnerability should prioritize immediate patching of affected WPThumb versions to the latest secure release. Organizations should implement network-level restrictions that prevent outbound requests to internal network ranges, effectively blocking potential exploitation attempts. Input validation controls must be strengthened to ensure that all external URLs are properly sanitized and validated before processing. The implementation of web application firewalls can provide additional protection layers by monitoring and filtering suspicious requests. According to CWE standards, this vulnerability maps to CWE-918 which specifically addresses server-side request forgery vulnerabilities. From an ATT&CK framework perspective, this vulnerability aligns with techniques such as T1071.004 for application layer protocol and T1566 for phishing with a malicious attachment, as attackers can use this vulnerability to gain initial access or pivot within compromised environments. Organizations should also conduct thorough security assessments of their WordPress installations to identify any other potentially vulnerable plugins or components that may exhibit similar SSRF characteristics.