CVE-2019-10675 in WordPress
Summary
by MITRE
** DISPUTED ** WordPress 5.1.1 allows remote authenticated authors to obtain sensitive information via a modified PNG file to the wp-admin/media-new.php?browser-uploader Media Uploader feature, which reveals the full path in a wp-includes/functions.php exif_imagetype() error message, even when the "display_errors = Off" setting is used and wp_config.php has debugging disabled. NOTE: the vendor cannot reproduce this.
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Analysis
by VulDB Data Team • 08/21/2023
This vulnerability affects WordPress versions up to 5.1.1 and represents a sensitive information disclosure issue that occurs through the media uploader functionality. The flaw exists in the wp-admin/media-new.php endpoint where authenticated users can upload modified PNG files through the browser-uploader feature. When such files are processed, the system reveals the full server path through an error message generated by the exif_imagetype() function located in wp-includes/functions.php. This represents a significant security concern as it provides attackers with detailed system information that could aid in further exploitation attempts.
The technical mechanism behind this vulnerability involves the improper handling of image file validation within WordPress's media processing pipeline. Even when standard security measures are in place such as "display_errors = Off" configuration and disabled debugging in wp-config.php, the vulnerability persists because the exif_imagetype() function generates error messages that contain the full file path regardless of these security settings. This behavior demonstrates a fundamental flaw in how WordPress handles file validation errors, particularly for image processing functions that should not expose system information to authenticated users. The vulnerability operates under CWE-200 which specifically addresses improper error handling and information exposure.
The operational impact of this vulnerability extends beyond simple information disclosure as it provides attackers with critical system path information that can be leveraged in subsequent attacks. The full server path exposure enables attackers to understand the directory structure and potentially identify other vulnerabilities or misconfigurations within the system. This information disclosure can be particularly damaging when combined with other reconnaissance efforts, as it provides attackers with the exact locations of WordPress core files and potentially sensitive directories. The vulnerability affects authenticated users which means it can be exploited by compromised accounts or insider threats, making it particularly concerning for organizations with multiple user roles.
The disputed nature of this vulnerability stems from the vendor's inability to reproduce the issue, which creates uncertainty about the actual exploitability and severity. However, the potential for information disclosure remains significant regardless of reproduction status, as the described mechanism could theoretically occur under certain conditions. Organizations should consider this vulnerability as a potential risk and implement appropriate mitigations. The ATT&CK framework categorizes this under T1083 - File and Directory Discovery, as the vulnerability enables attackers to gather system information through file processing mechanisms. The security community should treat this as a potential vector for reconnaissance and privilege escalation attacks, particularly when combined with other vulnerabilities in the WordPress ecosystem. Proper input validation and error handling should be implemented to prevent such information exposure, and organizations should ensure their WordPress installations are updated to versions that address this concern.