CVE-2021-41683 in JerryScript
Summary
by MITRE • 06/20/2022
There is a stack-overflow at ecma-helpers.c:326 in ecma_get_lex_env_type in JerryScript 2.4.0
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 06/20/2022
The vulnerability identified as CVE-2021-41683 represents a critical stack overflow condition within the JerryScript JavaScript engine version 2.4.0. This issue manifests in the ecma_get_lex_env_type function located at ecma-helpers.c line 326, where improper input validation leads to excessive stack consumption during lexical environment type processing. The flaw arises from inadequate bounds checking when handling specific JavaScript constructs that trigger the function's recursive or iterative processing patterns, ultimately resulting in stack memory corruption that can be exploited for arbitrary code execution.
This vulnerability falls under the CWE-121 stack-based buffer overflow classification, specifically targeting the stack memory management within the JavaScript engine's execution environment. The attack surface is particularly concerning as it occurs during normal JavaScript execution flows when parsing and processing lexical environments, making it applicable to any application or service utilizing JerryScript for JavaScript interpretation. The stack overflow condition can be triggered through carefully crafted JavaScript code that exploits the function's handling of nested or complex lexical scope constructs, potentially leading to privilege escalation or denial of service scenarios.
The operational impact of CVE-2021-41683 extends beyond simple crash conditions to encompass potential remote code execution capabilities when exploited in contexts where JerryScript is embedded in web applications, IoT devices, or embedded systems. Attackers can leverage this vulnerability by crafting malicious JavaScript payloads that cause the engine to repeatedly call ecma_get_lex_env_type with escalating stack frame requirements until the stack overflow occurs. This represents a significant concern for embedded systems and IoT devices that rely on JerryScript for scripting capabilities, as these environments often lack standard exploit mitigations such as stack canaries or address space layout randomization.
Security professionals should consider this vulnerability in relation to ATT&CK technique T1059.007 for JavaScript execution and T1203 for exploitation of memory corruption vulnerabilities. The mitigation strategy should prioritize immediate patching of JerryScript to version 2.4.1 or later where the stack overflow has been addressed through proper input validation and stack frame size limiting. Additionally, implementing runtime protections such as stack canary instrumentation, heap-based buffer overflow detection, and input sanitization of JavaScript code can provide defense-in-depth measures. Organizations should also conduct thorough code reviews of any custom JavaScript implementations that interact with JerryScript to identify potential indirect exploitation vectors, particularly in environments where untrusted JavaScript input is processed. The vulnerability highlights the importance of rigorous memory management practices in embedded JavaScript engines and underscores the need for comprehensive testing of edge cases in lexical environment handling functions.