CVE-2025-62494 (GCVE-0-2025-62494)
Vulnerability from cvelistv5
Published
2025-10-16 15:51
Modified
2025-10-16 17:46
Severity ?
7.1 (High) - CVSS:4.0/AV:A/AC:H/AT:P/PR:L/UI:P/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L
CWE
  • CWE-704 - Incorrect Type Conversion or Cast
Summary
A type confusion vulnerability exists in the handling of the string addition (+) operation within the QuickJS engine. * The code first checks if the left-hand operand is a string. * It then attempts to convert the right-hand operand to a primitive value using JS_ToPrimitiveFree. This conversion can trigger a callback (e.g., toString or valueOf). * During this callback, an attacker can modify the type of the left-hand operand in memory, changing it from a string to a different type (e.g., an object or an array). * The code then proceeds to call JS_ConcatStringInPlace, which still treats the modified left-hand value as a string. This mismatch between the assumed type (string) and the actual type allows an attacker to control the data structure being processed by the concatenation logic, resulting in a type confusion condition. This can lead to out-of-bounds memory access, potentially resulting in memory corruption and arbitrary code execution in the context of the QuickJS runtime.
References
cve-coordination@google.comhttps://bellard.org/quickjs/Changelog
cve-coordination@google.comhttps://issuetracker.google.com/434193023
Impacted products
Vendor Product Version
QuickJS QuickJS Version: 2025-04-26
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