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        "dateReserved": "2023-08-01T10:38:03.032Z",
        "datePublished": "2023-09-13T08:05:10.274Z",
        "dateUpdated": "2026-06-23T17:19:09.321Z"
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                            "value": "The specific conditions where the stack-protector fails to give the desired level of protection are when:\n\n\n<ul>\n    <li>using GCC (all unpatched versions) targeting AArch64</li>\n    <li>and when the -fstack-protector option is used</li>\n    <li>and when the program uses C99-style dynamically-sized local variables or alloca()</li>\n</ul>\n<p>And to be exploitable there must also be a prior vulnerability in the\n program such that an attacker can cause a buffer overflow in these \nlocal variables that overwrites saved register values in the stack.</p>\n\n<br>"
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                            "value": "<p>\n</p><p>**DISPUTED** A failure in the -fstack-protector feature in GCC-based toolchains \nthat target AArch64 allows an attacker to exploit an existing buffer \noverflow in dynamically-sized local variables in your application \nwithout this being detected. This stack-protector failure only applies \nto C99-style dynamically-sized local variables or those created using \nalloca(). The stack-protector operates as intended for statically-sized \nlocal variables.</p><p>The default behavior when the stack-protector \ndetects an overflow is to terminate your application, resulting in \ncontrolled loss of availability. An attacker who can exploit a buffer \noverflow without triggering the stack-protector might be able to change \nprogram flow control to cause an uncontrolled loss of availability or to\n go further and affect confidentiality or integrity. NOTE: The GCC project argues that this is a missed hardening bug and not a vulnerability by itself.</p>\n\n<p></p>"
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                            "value": "CAPEC-100 Overflow Buffers"
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