Linux Distros 未修补的漏洞: CVE-2024-35871

high Nessus 插件 ID 228781

简介

Linux/Unix 主机上安装的一个或多个程序包存在漏洞,但供应商表示不会修补此漏洞。

描述

Linux/Unix 主机中安装的一个或多个程序包受到一个漏洞影响,而供应商没有提供补丁程序。

- 在 Linux 内核中,已解决以下漏洞: riscv: process: Fix kernel gp leakage childregs represents the registers which are active for the new thread in user context. For a kernel thread, childregs->gp is never used since the kernel gp is not touched by switch_to. For a user mode helper, the gp value can be observed in user space after execve or possibly by other means. [From the email thread] The /* Kernel thread */ comment is somewhat inaccurate in that it is also used for user_mode_helper threads, which exec a user process, e.g. /sbin/init or when /proc/sys/kernel/core_pattern is a pipe. Such threads do not have PF_KTHREAD set and are valid targets for ptrace etc. even before they exec. childregs is the *user* context during syscall execution and it is observable from userspace in at least five ways: 1. kernel_execve does not currently clear integer registers, so the starting register state for PID 1 and other user processes started by the kernel has sp = user stack, gp = kernel
__global_pointer$, all other integer registers zeroed by the memset in the patch comment. This is a bug in its own right, but I'm unwilling to bet that it is the only way to exploit the issue addressed by this patch. 2. ptrace(PTRACE_GETREGSET): you can PTRACE_ATTACH to a user_mode_helper thread before it execs, but ptrace requires SIGSTOP to be delivered which can only happen at user/kernel boundaries. 3.
/proc/*/task/*/syscall: this is perfectly happy to read pt_regs for user_mode_helpers before the exec completes, but gp is not one of the registers it returns. 4. PERF_SAMPLE_REGS_USER: LOCKDOWN_PERF normally prevents access to kernel addresses via PERF_SAMPLE_REGS_INTR, but due to this bug kernel addresses are also exposed via PERF_SAMPLE_REGS_USER which is permitted under LOCKDOWN_PERF. I have not attempted to write exploit code. 5. Much of the tracing infrastructure allows access to user registers. I have not attempted to determine which forms of tracing allow access to user registers without already allowing access to kernel registers. (CVE-2024-35871)

请注意,Nessus 依赖供应商报告的程序包是否存在进行判断。

解决方案

目前尚未有任何已知的解决方案。

插件详情

严重性: High

ID: 228781

文件名: unpatched_CVE_2024_35871.nasl

版本: 1.1

类型: local

代理: unix

系列: Misc.

发布时间: 2025/3/5

最近更新时间: 2025/3/5

支持的传感器: Nessus Agent, Nessus

风险信息

VPR

风险因素: Medium

分数: 5.9

CVSS v2

风险因素: High

基本分数: 7.2

时间分数: 5.3

矢量: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS 分数来源: CVE-2024-35871

CVSS v3

风险因素: High

基本分数: 7

时间分数: 6.1

矢量: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

时间矢量: CVSS:3.0/E:U/RL:O/RC:C

漏洞信息

必需的 KB 项: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched

易利用性: No known exploits are available

漏洞发布日期: 2024/5/10

参考资料信息

CVE: CVE-2024-35871