Editing Vulnerabilities

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* For select types implemented by WebKit (such as JSC::JSFunction), certain pointer fields are XOR'ed by a cryptographic key generated at runtime. The key is generated once every process launch, one must recover it to unpoison the pointers.
* For select types implemented by WebKit (such as JSC::JSFunction), certain pointer fields are XOR'ed by a cryptographic key generated at runtime. The key is generated once every process launch, one must recover it to unpoison the pointers.
=== Flush-to-Zero and Denormals-are-Zero Floating-Point environment ===
[https://en.wikipedia.org/wiki/Subnormal_number Subnormal numbers] (also called as denormal numbers in IEEE 754 documents before the 2008 version) are treated as 0 on the PlayStation runtime environment. This isn't technically a security technique but it does inhibit any exploit that uses floating-point numbers for read/write.
An example entrypoint is WebKit where exploits have commonly used double arrays with incorrect length to read/write certain memory areas to gain arbitrary read/write or even code execution. With FTZ/DAZ, the possible 64-bit values one can write have become even more limited. Reads using double arrays are also affected. Even if the bit pattern is nonzero but encodes a subnormal, it will be read by the JavaScript engine as 0.


== Kernel ==
== Kernel ==
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