CVE-2026-105677 in Ghost
Summary
by MITRE • 10/06/2026
Ghost is a Node.js content management system. From 6.10.3 until 6.64.0, a vulnerability in how Ghost loads theme translation files allowed an authenticated Administrator to execute arbitrary code on the server via a crafted theme. This issue is fixed in version 6.64.0.
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Analysis
by VulDB Data Team • 10/06/2026
The identified vulnerability resides within the core architecture of Ghost, a popular Node.js-based content management system designed for professional publishing and blogging platforms. Specifically affecting versions ranging from 6.10.3 through 6.64.0, this flaw stems from an insufficient validation mechanism when processing theme translation files. In typical CMS operations, themes define the visual presentation and structural layout of a website, while translation files handle localization strings to support multiple languages. The system was designed to load these JSON-based or similar structured data files without applying strict sanitization protocols on their content before execution within the server-side rendering context. This architectural oversight creates a pathway for code injection attacks targeting users with administrative privileges.
The technical nature of this flaw classifies as an Insecure Deserialization vulnerability, which aligns closely with CWE-502 in the Common Weakness Enumeration database. When an authenticated Administrator uploads or modifies a theme package containing specially crafted translation files, the application parses these inputs without adequately verifying their integrity or structure against expected schemas. Because Node.js environments often allow dynamic evaluation of data structures during runtime, maliciously constructed objects within the translation file can trigger unintended side effects. An attacker leveraging this weakness does not need to bypass authentication since they must already possess Administrator access, but they exploit the trust placed in administrative actions to execute arbitrary JavaScript code on the host server. This represents a significant escalation from simple cross-site scripting or content manipulation, as it grants full control over the underlying operating system processes running the Ghost instance.
The operational impact of this vulnerability is severe due to its potential for complete system compromise. Once an attacker successfully injects and executes arbitrary code through the theme translation loader, they can perform a wide array of malicious activities including reading sensitive configuration files such as database credentials, exfiltrating user data stored within the CMS, installing persistent backdoors, or pivoting further into internal network segments depending on the server's exposure. The existence of this flaw undermines the integrity and confidentiality guarantees provided by the platform to its enterprise users who rely on Ghost for critical digital presence management. It highlights a broader industry challenge where convenience in theme development is prioritized over rigorous input validation at the serialization layer, allowing trusted roles to inadvertently become vectors for remote code execution if proper safeguards are not enforced during file parsing operations.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. The primary and most effective solution is to upgrade all affected Ghost instances to version 6.64.0 or later, where the developers have implemented stricter validation rules for theme assets including translation files. For environments that cannot immediately patch due to compatibility constraints with custom themes, administrators should enforce strict file upload policies by whitelisting allowed extensions and validating JSON structures against a predefined schema before processing. Additionally, running Ghost instances within restricted containerized environments or using sandboxing techniques can limit the blast radius of any successful exploitation attempt. Security teams should also audit existing theme packages for anomalies in translation files and disable dynamic theme loading features if they are not actively utilized by the organization to reduce the attack surface associated with this specific code path.