Marks-Man
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Tracked as CVE-2021-30554, the high severity flaw concerns a use after free vulnerability in WebGL (aka Web Graphics Library), a JavaScript API for rendering interactive 2D and 3D graphics within the browser.
Description
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.
Extended Description
The use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system's reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:
If the newly allocated data chances to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
Description
Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.
Extended DescriptionThe use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system's reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:
- Error conditions and other exceptional circumstances.
- Confusion over which part of the program is responsible for freeing the memory.
If the newly allocated data chances to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.