Linux Distros 未修補弱點:CVE-2021-47227

medium Nessus Plugin ID 229818

概要

Linux/Unix 主機上安裝的一個或多個套件存有弱點,供應商表示將不會修補。

說明

Linux/Unix 主機上安裝了一個或多個受到弱點影響的套件,且供應商未提供可用的修補程式。

- 在 Linux 核心中,已解決下列弱點: x86/fpu: Prevent state corruption in
__fpu__restore_sig() The non-compacted slowpath uses __copy_from_user() and copies the entire user buffer into the kernel buffer, verbatim. This means that the kernel buffer may now contain entirely invalid state on which XRSTOR will #GP. validate_user_xstate_header() can detect some of that corruption, but that leaves the onus on callers to clear the buffer. Prior to XSAVES support, it was possible just to reinitialize the buffer, completely, but with supervisor states that is not longer possible as the buffer clearing code split got it backwards. Fixing that is possible but not corrupting the state in the first place is more robust. Avoid corruption of the kernel XSAVE buffer by using copy_user_to_xstate() which validates the XSAVE header contents before copying the actual states to the kernel. copy_user_to_xstate() was previously only called for compacted-format kernel buffers, but it works for both compacted and non-compacted forms. Using it for the non-compacted form is slower because of multiple __copy_from_user() operations, but that cost is less important than robust code in an already slow path. [ Changelog polished by Dave Hansen ] (CVE-2021-47227)

請注意,Nessus 依賴供應商報告的套件存在。

解決方案

目前尚未有已知的解決方案。

Plugin 詳細資訊

嚴重性: Medium

ID: 229818

檔案名稱: unpatched_CVE_2021_47227.nasl

版本: 1.1

類型: local

代理程式: unix

系列: Misc.

已發布: 2025/3/5

已更新: 2025/3/5

支援的感應器: Nessus Agent, Nessus

風險資訊

VPR

風險因素: Medium

分數: 4.4

CVSS v2

風險因素: Medium

基本分數: 4.6

時間性分數: 3.4

媒介: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

CVSS 評分資料來源: CVE-2021-47227

CVSS v3

風險因素: Medium

基本分數: 5.5

時間性分數: 4.8

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

時間媒介: CVSS:3.0/E:U/RL:O/RC:C

弱點資訊

必要的 KB 項目: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched

可輕鬆利用: No known exploits are available

弱點發布日期: 2022/1/20

參考資訊

CVE: CVE-2021-47227