CVE-2026-114574 in massCode
Summary
by MITRE • 10/22/2026
A security vulnerability has been detected in massCodeIO massCode 5.10. Affected is an unknown function of the file src/main/api/index.ts of the component Local HTTP Service. Such manipulation leads to information disclosure. It is possible to launch the attack remotely. The exploit has been disclosed publicly and may be used. The name of the patch is d25d8fa3f5a1e34285c8634f18729650c0c05cda. It is advisable to implement a patch to correct this issue.
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Analysis
by VulDB Data Team • 10/22/2026
The vulnerability identified in massCodeIO version 5.10 represents a critical information disclosure flaw within the Local HTTP Service component, specifically located in the source file src/main/api/index.ts. This defect arises from an unknown function that fails to properly restrict access or sanitize output when handling requests directed at local endpoints. In typical implementations of such services, developers often assume that because the service binds to localhost interfaces like 127.0.0.1, it is inherently secure against remote exploitation. However, this assumption can be flawed if the application logic does not strictly validate the origin or context of incoming requests, particularly in environments where network tunneling tools are available. The presence of a publicly disclosed patch with the hash d25d8fa3f5a1e34285c8634f18729650c0c05cda indicates that the maintainers have acknowledged this oversight and provided a code-level correction to mitigate the exposure.
From a technical perspective, this vulnerability aligns with CWE-200, which categorizes issues related to the exposure of sensitive information to unauthorized actors. The core issue likely involves improper access control or insufficient input validation within the API endpoint logic. When an attacker interacts with the Local HTTP Service, they may be able to trigger specific functions that return internal application state, configuration details, user data, or other proprietary information that was not intended for external consumption. Although the service is designated as local, modern development environments and CI/CD pipelines often utilize tools like SSH tunneling, ngrok, or similar proxy services that can forward traffic from public internet addresses to localhost ports. This architectural reality means that a vulnerability in a locally bound service is effectively exploitable remotely if such forwarding mechanisms are present on the host machine.
The operational impact of this information disclosure can be severe depending on the nature of the data exposed. If the leaked information includes authentication tokens, session IDs, database connection strings, or internal API keys, an attacker could leverage these credentials to escalate privileges within the application or access backend systems directly. This scenario is consistent with ATT&CK technique T1078, which covers Valid Accounts and potentially T1539 if it leads to direct data exfiltration from local storage. The fact that the exploit has been disclosed publicly significantly increases the risk landscape, as automated scanners and malicious actors can readily deploy proof-of-concept attacks against unpatched instances without needing specialized knowledge of the internal codebase.
To mitigate this vulnerability, immediate implementation of the provided patch is essential for all systems running massCodeIO version 5.10 or affected versions prior to the fix. Beyond applying the software update, organizations should review their network configurations to ensure that local services are not inadvertently exposed via tunneling tools unless absolutely necessary and properly secured with additional authentication layers such as TLS client certificates or IP whitelisting at the firewall level. It is also advisable to conduct a broader audit of other API endpoints within the application to identify similar patterns where localhost binding might create a false sense of security. Regular vulnerability assessments and penetration testing that include local service enumeration can help detect these types of misconfigurations before they are exploited in production environments.