vendor:
N/A
by:
Anonymous
8.8
CVSS
HIGH
Type Confusion
843
CWE
Product Name: N/A
Affected Version From: N/A
Affected Version To: N/A
Patch Exists: NO
Related CWE: N/A
CPE: N/A
Metasploit:
N/A
Other Scripts:
N/A
Platforms Tested: N/A
2020
CheckJsArrayKills Vulnerability
This vulnerability is similar to the previous issues 1457, 1459 (MSRC 42551, MSRC 42552). If a JavaScript function is used as a constructor, it sets the new object's '__proto__' to its 'prototype'. The JIT compiler uses NewScObjectNoCtor instructions to perform it, but those instructions are not checked by CheckJsArrayKills which is used to validate the array information. A proof-of-concept code is provided in the text.
Mitigation:
The user should ensure that the JavaScript functions are not used as constructors.