CVE-2021-23436: Access of Resource Using Incompatible Type (Type Confusion)

September 1, 2021 (updated September 10, 2021)

A type confusion vulnerability can lead to a bypass of CVE-2020-28477 when the user-provided keys used in the path parameter are arrays. In particular, this bypass is possible because the condition (p === "__proto__" || p === "constructor") in applyPatches_ returns false if p is ['__proto__'] (or ['constructor']). The === operator (strict equality operator) returns false if the operands have different type.

References

nvd.nist.gov/vuln/detail/CVE-2021-23436

Code Behaviors & Features

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