CVE-2018-18955

描述

In the Linux kernel 4.15.x through 4.19.x before 4.19.2, map_write() in kernel/user_namespace.c allows privilege escalation because it mishandles nested user namespaces with more than 5 UID or GID ranges. A user who has CAP_SYS_ADMIN in an affected user namespace can bypass access controls on resources outside the namespace, as demonstrated by reading /etc/shadow. This occurs because an ID transformation takes place properly for the namespaced-to-kernel direction but not for the kernel-to-namespaced direction.

如何修補 CVE-2018-18955

要修補 CVE-2018-18955,請將受影響套件升級到下列已修補版本。

• —升級至 4.18.20-1 或更新版本

CVE-2018-18955 正在被利用嗎?

中等 — EPSS 為 7.6%,可持續追蹤但非最高優先。

受影響套件(1)

• from 0, < 4.18.20-1

CVSS 分數

參考連結(1)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2018-18955