CVE-2023-34868 in Jerryscript
Summary
by MITRE • 06/14/2023
Jerryscript 3.0 (commit 05dbbd1) was discovered to contain an Assertion Failure via the parser_parse_for_statement_start at jerry-core/parser/js/js-parser-statm.c.
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Analysis
by VulDB Data Team • 01/09/2026
The vulnerability identified as CVE-2023-34868 affects Jerryscript version 3.0, specifically manifesting in the parser_parse_for_statement_start function within the jerry-core/parser/js/js-parser-statm.c file. This represents a critical assertion failure that occurs during the parsing phase of JavaScript code execution, potentially leading to unexpected program termination or system instability. The issue arises from insufficient input validation within the parser component, which is responsible for analyzing and interpreting JavaScript syntax structures.
The technical flaw stems from an assertion that fails when processing specific malformed or unexpected input patterns within for statement parsing contexts. When the parser encounters certain combinations of tokens or structural elements within for loops, the assertion condition designed to validate expected parsing states becomes invalid, causing the program to terminate abruptly. This assertion failure demonstrates a lack of proper error handling and input sanitization within the JavaScript engine's parsing logic. The vulnerability falls under CWE-617, which addresses reachable assertions, and represents a classic example of insufficient validation of assertions in security-critical code paths.
Operationally, this vulnerability presents significant risks to systems utilizing Jerryscript as their JavaScript engine, particularly in embedded environments or IoT devices where the engine may process untrusted input from external sources. An attacker could potentially craft malicious JavaScript code that triggers this assertion failure, leading to denial of service conditions or, in more sophisticated scenarios, creating opportunities for further exploitation. The impact extends beyond simple service disruption as the parser failure could affect the entire JavaScript execution environment, potentially compromising system stability and availability. This vulnerability aligns with ATT&CK technique T1203, which covers Exploitation for Client Execution, as it could enable attackers to manipulate JavaScript execution environments.
Mitigation strategies should prioritize immediate patching of affected Jerryscript versions to address the assertion failure in the parser component. Organizations should implement strict input validation and sanitization measures when processing JavaScript code, particularly in environments where external inputs are accepted. Additionally, deploying runtime monitoring and intrusion detection systems can help identify anomalous parsing behavior that might indicate exploitation attempts. The fix should include robust error handling mechanisms within the parser to gracefully manage unexpected input patterns rather than allowing assertion failures to terminate execution. Security teams should also consider implementing sandboxing techniques to isolate JavaScript execution environments and limit the potential impact of such vulnerabilities. Regular security assessments of embedded JavaScript engines and comprehensive testing of parsing logic with various input patterns can help prevent similar issues from emerging in future deployments.