Out-of-Bounds Affecting libgcc package, versions <0:7.3.1-17.amzn2

Note: Versions mentioned in the description apply only to the upstream libgcc package and not the libgcc package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2 relevant fixed versions and status.

DISPUTEDA failure in the -fstack-protector feature in GCC-based toolchains that target AArch64 allows an attacker to exploit an existing buffer overflow in dynamically-sized local variables in your application without this being detected. This stack-protector failure only applies to C99-style dynamically-sized local variables or those created using alloca(). The stack-protector operates as intended for statically-sized local variables.

The default behavior when the stack-protector detects an overflow is to terminate your application, resulting in controlled loss of availability. An attacker who can exploit a buffer overflow without triggering the stack-protector might be able to change program flow control to cause an uncontrolled loss of availability or to 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.

• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-4039
• https://developer.arm.com/Arm%20Security%20Center/GCC%20Stack%20Protector%20Vulnerability%20AArch64
• https://github.com/metaredteam/external-disclosures/security/advisories/GHSA-x7ch-h5rf-w2mf