CVE-2026-2769 is a use-after-free vulnerability located within the Storage: IndexedDB component of Mozilla Firefox. Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, leading to undefined behavior such as memory corruption, crashes, or arbitrary code execution. This specific flaw affects Firefox versions earlier than 148, Firefox ESR versions earlier than 115.33, and 140.8. IndexedDB is a web standard for client-side storage of significant amounts of structured data, commonly used by web applications. An attacker can exploit this vulnerability by crafting malicious web content that interacts with the IndexedDB API, triggering the use-after-free condition. This can result in execution of arbitrary code within the context of the browser, potentially allowing attackers to bypass security restrictions, steal sensitive information, or cause denial of service by crashing the browser. No CVSS score has been assigned yet, and no known exploits have been reported in the wild, but the vulnerability is publicly disclosed and considered serious. The lack of authentication or user interaction requirements beyond visiting a malicious web page increases the risk. The vulnerability underscores the importance of memory safety in browser components that handle complex data storage and retrieval. Mozilla is expected to release patches addressing this issue, and users should upgrade promptly to mitigate risk.

The impact of CVE-2026-2769 is significant for organizations and individual users relying on Firefox for web browsing. Successful exploitation can lead to arbitrary code execution within the browser process, compromising confidentiality by exposing sensitive data, integrity by allowing manipulation of browser state or data, and availability by causing crashes or denial of service. This can facilitate further attacks such as malware installation, credential theft, or lateral movement within networks. Given Firefox's widespread use across government, enterprise, and consumer environments, the vulnerability poses a broad risk. Organizations with strict security requirements, such as financial institutions, healthcare providers, and critical infrastructure operators, are particularly vulnerable to targeted exploitation. The absence of known exploits currently provides a window for proactive mitigation, but the public disclosure increases the likelihood of future exploit development. The vulnerability also threatens privacy-conscious users who rely on Firefox's security features. Overall, the threat could lead to significant operational disruption and data breaches if left unaddressed.

To mitigate CVE-2026-2769, organizations and users should prioritize updating Firefox to version 148 or later, or the corresponding ESR versions 115.33 and 140.8 once patches are released. Until patches are available, consider disabling or restricting IndexedDB functionality via browser configuration or enterprise policies to reduce attack surface. Employ browser security features such as sandboxing, strict content security policies (CSP), and disabling JavaScript on untrusted sites to limit exploitation vectors. Network-level controls like web filtering and intrusion prevention systems can block access to known malicious sites exploiting this vulnerability. Regularly monitor Mozilla security advisories and threat intelligence feeds for updates or exploit reports. Educate users on the risks of visiting untrusted websites and the importance of timely browser updates. For high-security environments, consider using browser isolation technologies or alternative browsers with no known vulnerabilities in IndexedDB. Conduct internal vulnerability assessments and penetration tests focusing on browser security to detect potential exploitation attempts. Implement endpoint detection and response (EDR) solutions to identify suspicious browser behavior indicative of exploitation.