CVE-2026-103288 in Ghost
Summary
by MITRE • 10/01/2026
Ghost, an open-source publishing platform, contains an input validation flaw in its comment like feature in versions from 5.9.0 before 6.44.1. An authenticated member can delete comment likes or dislikes belonging to other users that they are not authorized to delete, resulting in an authorization bypass and unauthorized modification of comment engagement data.
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Analysis
by VulDB Data Team • 10/01/2026
The vulnerability identified within the Ghost open-source publishing platform represents a critical failure in server-side access control mechanisms, specifically affecting versions ranging from 5.9.0 up to but not including 6.44.1. This flaw is located within the functionality that handles comment engagement metrics, particularly the ability for users to like or dislike comments posted by others on articles and posts hosted on a Ghost instance. The core technical issue stems from an insufficient validation of user permissions when processing requests related to deleting likes or dislikes. In a properly secured application architecture, any action that modifies data belonging to another entity must verify that the initiating request originates from the owner of that specific data record or possesses elevated administrative privileges capable of overriding such restrictions. However, in this instance, the backend API endpoint responsible for removing engagement records fails to cross-reference the identity of the authenticated user making the deletion request against the ownership metadata associated with each individual like or dislike entry.
This architectural oversight allows any authenticated member of a Ghost site to manipulate the engagement statistics of other users by simply issuing an HTTP DELETE request targeting specific comment interaction identifiers without providing proof of ownership for those interactions. Because the system relies primarily on session authentication rather than granular object-level authorization checks, it assumes that if a user is logged in and has general permissions to interact with comments, they should also have permission to remove any such interaction regardless of who originally created it. This constitutes a classic Broken Access Control vulnerability where the application enforces restrictions based on role-based access control at a coarse level but fails to implement fine-grained checks necessary for data integrity regarding user-specific assets. The absence of these checks means that the confidentiality and integrity aspects of the system are compromised, as users cannot trust that their engagement signals will remain intact against malicious or accidental interference by other registered members.
The operational impact of this vulnerability extends beyond simple annoyance to include potential manipulation of content visibility metrics and social proof indicators on a publishing platform. Ghost relies heavily on community interaction features such likes and dislikes to gauge reader sentiment and potentially influence algorithmic sorting or highlighting of popular content. By allowing unauthorized deletion, an attacker can artificially suppress the perceived popularity of specific comments made by other users, thereby skewing the narrative around particular articles or discussions. This could be exploited for malicious purposes such as silencing dissenting opinions, harassing specific community members by removing their supportive interactions, or creating a false impression that certain content is less engaging than it actually is. Furthermore, in environments where engagement metrics are used to determine featured posts or drive traffic analytics, this manipulation can distort business intelligence and editorial decisions derived from these statistics.
From a classification perspective, this vulnerability aligns with CWE-284 Improper Access Control, specifically highlighting the failure to enforce proper authorization checks for sensitive operations. It also maps directly to MITRE ATT&CK technique T1078 Valid Accounts, as it requires valid authentication credentials but abuses them to perform unauthorized actions against resources owned by other users. The exploitation path is straightforward and does not require complex payload construction or buffer overflow techniques; instead, it leverages standard API interactions that are easily automated using common web testing tools like Burp Suite or custom scripts written in Python with the requests library. An attacker would need only to identify a target comment's engagement ID and issue a deletion request while authenticated as any other user on the platform.
Mitigation strategies must prioritize immediate patching of the Ghost installation to version 6.44.1 or later, where this authorization logic has been corrected to enforce strict ownership verification before processing deletion requests. For organizations unable to upgrade immediately due to compatibility constraints with custom themes or integrations, temporary compensating controls should be implemented at the web application firewall level if available. These controls can include rate limiting on comment-related API endpoints and stricter validation rules that reject modification requests unless the user ID in the session matches the owner ID of the targeted engagement record. Additionally, developers reviewing similar codebases within their own infrastructure should audit all CRUD operations for object-level authorization checks to prevent analogous flaws where users might modify or delete resources belonging to others due to missing ownership validations. Regular security audits focusing on access control logic are essential to maintain the integrity of user-generated content and ensure that platform metrics remain a reliable reflection of genuine community engagement rather than subject to manipulation by authenticated actors with malicious intent.