CVE-2026-118435 in escargot
Summary
by MITRE • 10/28/2026
Out-of-bounds write vulnerability in Samsung Open Source escargot allows Buffer Manipulation.
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Analysis
by VulDB Data Team • 10/28/2026
The identified vulnerability represents a critical memory safety flaw within the Escargot JavaScript engine, an open-source project maintained by Samsung that serves as the core runtime for Tizen and other embedded Linux distributions. This specific issue is classified as an out-of-bounds write, which falls under the Common Weakness Enumeration category CWE-787: Out-of-Bounds Write. In practical terms, this means that during the execution of JavaScript code, the engine fails to properly validate memory access boundaries when manipulating buffers or array structures. Instead of halting execution upon detecting an invalid index or size parameter, Escargot proceeds to write data beyond the allocated limits of a buffer in heap memory. This behavior is particularly dangerous because it allows for arbitrary memory modification rather than just reading sensitive information, which significantly expands the potential attack surface compared to out-of-bounds read vulnerabilities.
From a technical perspective, this flaw likely stems from insufficient bounds checking during operations such as array resizing, string concatenation, or typed buffer manipulation within the JIT (Just-In-Time) compiler or interpreter components of Escargot. When an attacker crafts malicious JavaScript input that triggers these specific code paths with carefully calculated indices, they can overwrite adjacent memory structures. This capability enables a technique known as heap grooming, where the attacker arranges objects in memory to control what lies next to the vulnerable buffer. By overwriting metadata or pointers associated with neighboring objects, the attacker can achieve arbitrary read and write primitives. These primitives are foundational for bypassing modern browser security mitigations such as Control Flow Integrity (CFI) and Data Execution Prevention (DEP), ultimately leading to remote code execution within the context of the application running Escargot.
The operational impact of this vulnerability is severe, particularly in environments where Escargot powers web views or embedded devices with limited sandboxing capabilities. An attacker who can trigger this flaw through a hosted website or a malicious script executed by an administrator could gain full control over the underlying operating system. This aligns with several tactics and techniques from the MITRE ATT&CK framework, specifically T1203: Exploitation for Client Execution if triggered via a web browser, and potentially T1059: Command and Scripting Interpreter if used to execute further payloads within the JavaScript context before escalating privileges. For IoT devices or smart TVs running Tizen OS, this could allow an attacker to install persistent malware, exfiltrate user data, or use the device as part of a botnet without any physical access required.
Mitigation strategies must focus on both immediate patching and long-term architectural improvements. The primary defense is applying vendor-provided security updates that include patches for Escargot, ensuring that bounds checks are strictly enforced in all memory allocation routines. Developers integrating Escargot should ensure their build configurations enable Address Sanitizer (ASan) or similar dynamic analysis tools during testing phases to detect such issues early. Furthermore, implementing strict Content Security Policies and disabling unnecessary JavaScript features can reduce the attack surface available to potential exploiters. For system administrators, it is crucial to isolate web-rendering processes using sandboxing mechanisms like SELinux policies or namespaces to limit the blast radius if a vulnerability in Escargot were successfully exploited. Regular audits of third-party dependencies are also essential to maintain visibility over known vulnerabilities in core runtime components that may not be directly visible to end-users but form the foundation of application security.