CVE-2017-9065 in WordPress
Summary
by MITRE
In WordPress before 4.7.5, there is a lack of capability checks for post meta data in the XML-RPC API.
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Analysis
by VulDB Data Team • 12/06/2022
The vulnerability identified as CVE-2017-9065 represents a critical authorization flaw in WordPress versions prior to 4.7.5, specifically within the XML-RPC API implementation. This issue stems from insufficient capability validation mechanisms that govern access to post metadata operations, creating a pathway for unauthorized users to manipulate or retrieve sensitive information. The vulnerability manifests when the XML-RPC API processes requests related to post meta data without properly verifying whether the requesting user possesses the necessary permissions to perform such operations. This flaw directly impacts the principle of least privilege and authorization controls that are fundamental to secure application design.
The technical exploitation of this vulnerability occurs through the XML-RPC interface which allows remote procedure calls to WordPress functions. Attackers can leverage this weakness to perform unauthorized actions on post meta data, potentially including reading, modifying, or deleting metadata associated with posts they should not have access to. The vulnerability is classified under CWE-284 Access Control, specifically addressing insufficient access control mechanisms in web applications. This weakness enables attackers to bypass normal authorization checks that should prevent users from accessing or modifying resources beyond their assigned permissions, representing a direct violation of the access control model that WordPress implements for its content management system.
The operational impact of CVE-2017-9065 extends beyond simple data exposure, as it can enable more sophisticated attacks including privilege escalation and data manipulation. An attacker with minimal privileges could potentially exploit this vulnerability to modify critical post metadata, alter content relationships, or even gain deeper access to the WordPress system through the manipulation of metadata fields that might contain sensitive configuration information. This vulnerability particularly affects WordPress installations that rely heavily on XML-RPC functionality for remote publishing or automated content management operations. The attack surface is broadened because XML-RPC is often enabled by default in WordPress installations, making this vulnerability accessible to attackers without requiring complex exploitation techniques.
Organizations and WordPress administrators should immediately upgrade to version 4.7.5 or later to remediate this vulnerability, as the patch addresses the core authorization check that was missing in the XML-RPC API implementation. Additionally, security teams should implement monitoring of XML-RPC API access patterns to detect anomalous usage that might indicate exploitation attempts. The mitigation strategy should include disabling XML-RPC functionality if it is not required for specific installations, as recommended by the WordPress security team. This vulnerability demonstrates the importance of comprehensive access control validation across all API endpoints and aligns with ATT&CK technique T1078 Valid Accounts, as it allows attackers to leverage existing user credentials to perform unauthorized actions within the WordPress system. The fix implemented in WordPress 4.7.5 ensures proper capability checks are enforced for all post meta data operations within the XML-RPC interface, thereby restoring the intended authorization boundaries that protect WordPress content from unauthorized manipulation.