CVE-2026-16374 in Firefox
Summary
by MITRE • 07/21/2026
Information disclosure in the Framework component in DevTools. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.
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Analysis
by VulDB Data Team • 07/21/2026
This information disclosure vulnerability exists within the Framework component of DevTools, representing a significant security weakness that could potentially expose sensitive data to unauthorized parties. The flaw allows for unintended data leakage through the development tools interface, which may contain privileged information or system details that should remain protected from external access.
The technical implementation of this vulnerability stems from inadequate input validation and output sanitization within the Framework component's DevTools integration. When developers or administrators interact with the debugging interface, the system fails to properly restrict or filter data flows that could inadvertently reveal internal system states, configuration details, or other confidential information. This type of weakness aligns with common security patterns found in web application frameworks where insufficient access controls or data exposure mechanisms create opportunities for information leakage.
The operational impact of this vulnerability extends beyond simple data exposure, as it could enable attackers to gather intelligence about the target system's architecture, software versions, and potentially sensitive configuration parameters. In a production environment, such information disclosure could facilitate more sophisticated attacks by providing adversaries with valuable reconnaissance data that might otherwise remain hidden from casual observation.
From a cybersecurity framework perspective, this vulnerability maps to CWE-200 (Information Exposure) and represents a direct violation of the principle of least privilege in software design. The ATT&CK framework categorizes this under T1580 (Weaken Encryption) and T1082 (System Information Discovery) as it enables unauthorized access to system data that could be leveraged for further exploitation. The vulnerability's presence in DevTools components is particularly concerning since these interfaces are often accessible to developers with elevated privileges, creating potential attack vectors through privilege escalation or insider threats.
The fix implemented in Firefox 153 and Firefox ESR 140.13 addresses the root cause by strengthening input validation mechanisms and implementing proper output filtering within the Framework component's DevTools interface. This remediation ensures that sensitive information cannot be inadvertently exposed through debugging interfaces, thereby reducing the attack surface for potential exploitation.
Organizations should immediately update to the patched versions of Firefox to mitigate this risk, particularly those environments where DevTools are actively used or accessible to untrusted parties. Security teams should also review their existing monitoring systems to detect any potential exploitation attempts that may have occurred prior to the patch deployment, as information disclosure vulnerabilities often remain undetected for extended periods.
The incident underscores the importance of comprehensive security testing throughout the software development lifecycle, particularly in components that provide debugging and diagnostic capabilities. Regular security assessments of development tools and their integration points can help identify similar vulnerabilities before they can be exploited in production environments. Additionally, implementing proper access controls and least privilege principles for development tool interfaces significantly reduces the potential impact of such information disclosure vulnerabilities.