CVE-2023-0045
MEDIUMLinux Kernel 3.16.68-3.17 - Branch Target Injection via prctl Syscall
Title source: llmExploitation Summary
EIP tracks 2 public exploits for CVE-2023-0045. PoCs published by es0j, ASkyeye.
AI-analyzed exploit summary This repository contains a proof-of-concept exploit for CVE-2023-0045, demonstrating a bypass of Spectre-BTI user space mitigations on Linux. The exploit leverages a timing window where the kernel fails to issue an IBPB immediately during a syscall, leaving processes vulnerable to branch target injection attacks.
Description
The current implementation of the prctl syscall does not issue an IBPB immediately during the syscall. The ib_prctl_set function updates the Thread Information Flags (TIFs) for the task and updates the SPEC_CTRL MSR on the function __speculation_ctrl_update, but the IBPB is only issued on the next schedule, when the TIF bits are checked. This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall. The patch that added the support for the conditional mitigation via prctl (ib_prctl_set) dates back to the kernel 4.9.176. We recommend upgrading past commit a664ec9158eeddd75121d39c9a0758016097fa96
Exploits (2)
This repository contains a proof-of-concept exploit for CVE-2023-0045, demonstrating a bypass of Spectre-BTI user space mitigations on Linux. The exploit leverages a timing window where the kernel fails to issue an IBPB immediately during a syscall, leaving processes vulnerable to branch target injection attacks.
This repository contains a proof-of-concept exploit for CVE-2023-0045, demonstrating a Spectre-BTI vulnerability in Linux kernel mitigations. The exploit shows that the kernel fails to issue an IBPB immediately during a syscall, leaving a window for attack.
References (5)
Scores
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N