CVE-2023-4039
GCC's-fstack-protector fails to guard dynamically-sized local variables on AArch64
**DISPUTED**A 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.
- Affected
- Arm Ltd · GNU · Arm GNU Toolchain · GCC
- CVSS v3.1 NVD
- 4.8 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS
- 1.04% chance of exploitation in the next 30 days, 63rd percentile
- Published
- 2023-09-13
- Updated
- 2026-10-14