CVE-2023-5753: 
NixOS vulnerability analysis and mitigation

CVE-2023-5753 is a vulnerability affecting the Zephyr Real-Time Operating System (RTOS) versions 3.4.0 and earlier. The vulnerability involves potential buffer overflows in the Bluetooth subsystem due to asserts being disabled in /subsys/bluetooth/host/hci_core.c. This issue was discovered and reported by Marco Ivaldi and was disclosed on October 24, 2023 (Zephyr Advisory).

The vulnerability stems from ineffective assertion checks in the Bluetooth subsystem's host component. Specifically, in the hcicore.c file, several functions including hciacl(), hcievent(), and hcievent_prio() use assertions to check buffer lengths, which could lead to buffer overflows when these assertions are disabled. The vulnerability has been assigned a CVSS v3.1 base score of 6.3 (Moderate) with vector: AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L (Zephyr Advisory).

If the unchecked input is attacker-controlled and crosses a security boundary, the impact could range from denial of service to potential arbitrary code execution. The vulnerability affects confidentiality, integrity, and availability at a low level, as indicated by the CVSS metrics (Zephyr Advisory).

The vulnerability has been fixed in the main branch for Zephyr 3.5 through pull request #63605. Users should upgrade to the patched version when available (Zephyr Advisory).