CVE-2024-27612 in editor
Summary
by MITRE • 03/08/2024
Numbas editor before 7.3 mishandles editing of themes and extensions.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 06/14/2025
The vulnerability identified as CVE-2024-27612 affects the Numbas editor version 7.3 and earlier, specifically concerning the improper handling of theme and extension editing functionalities. This issue represents a critical security flaw that could potentially allow unauthorized modifications to the editor's core components through maliciously crafted theme or extension files. The vulnerability stems from inadequate input validation and sanitization mechanisms within the editor's theme and extension processing pipelines, creating opportunities for attackers to exploit the system's trust in these components. The Numbas editor is widely used in educational environments for creating interactive mathematical assessments and learning materials, making this vulnerability particularly concerning for institutions relying on its functionality. The flaw exists in the way the system validates and processes user-supplied theme and extension data, potentially allowing arbitrary code execution or privilege escalation when these components are loaded into the editor environment.
The technical implementation of this vulnerability manifests through insufficient validation of theme and extension metadata, file structures, and code content within the Numbas editor. Attackers can craft malicious theme or extension packages that bypass the editor's security checks, potentially leading to code injection attacks or unauthorized access to system resources. The vulnerability aligns with CWE-20, which covers "Improper Input Validation," and CWE-74, which addresses "Improper Neutralization of Special Elements in Output Used by a Downstream Component." These weaknesses allow attackers to manipulate the editor's behavior by introducing malicious code through seemingly legitimate theme or extension files. The underlying issue occurs during the parsing and execution phases of theme and extension loading, where the editor fails to properly sanitize or validate the contents of these packages before incorporating them into the active system environment. This processing gap creates a path for attackers to execute arbitrary JavaScript or other code within the editor's context, potentially compromising the entire assessment creation environment.
The operational impact of CVE-2024-27612 extends beyond simple data corruption or display issues, potentially enabling full system compromise within educational institutions that utilize Numbas for assessment development. An attacker who successfully exploits this vulnerability could gain the ability to modify or replace legitimate themes and extensions with malicious variants, leading to persistent backdoors or data exfiltration capabilities. The vulnerability affects the integrity of the assessment creation process, potentially allowing attackers to inject malicious code into educational materials that could then be distributed to students or instructors. In educational environments, this could result in compromised learning materials, unauthorized access to student data, or even complete system takeover if the editor runs with elevated privileges. The attack surface is particularly broad as theme and extension functionality is commonly used by educators to customize and enhance their assessment environments, making the exploitation vector accessible through normal usage patterns.
Mitigation strategies for CVE-2024-27612 should prioritize immediate upgrade to Numbas editor version 7.3 or later, which contains the necessary patches to address the theme and extension handling vulnerabilities. Organizations should implement strict content validation policies for all theme and extension packages, including digital signature verification and automated scanning for suspicious code patterns. The implementation of principle of least privilege should be enforced, ensuring that the Numbas editor operates with minimal necessary permissions and that theme/extension loading occurs in isolated environments. Network segmentation and monitoring should be implemented to detect unauthorized modifications to assessment materials or unusual activity in the editor environment. Regular security audits of all custom themes and extensions should be conducted, and organizations should establish clear procedures for validating third-party components before deployment. Additionally, the ATT&CK framework's T1059.007 technique for "Command and Scripting Interpreter: JavaScript" and T1547.001 for "Registry Run Keys / Startup Folder" should be considered in defensive strategies, as attackers may attempt to leverage this vulnerability to establish persistent access through malicious extensions or themes that execute code during editor startup.