CVE-2020-11742

描述

An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of bad continuation handling in GNTTABOP_copy. Grant table operations are expected to return 0 for success, and a negative number for errors. The fix for CVE-2017-12135 introduced a path through grant copy handling where success may be returned to the caller without any action taken. In particular, the status fields of individual operations are left uninitialised, and may result in errant behaviour in the caller of GNTTABOP_copy. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to copy a grant, it hits the incorrect exit path. This returns success to the caller without doing anything, which may cause crashes or other incorrect behaviour.

如何修補 CVE-2020-11742

要修補 CVE-2020-11742,請將受影響套件升級到下列已修補版本。

• —升級至 4.12.2-r1 或更新版本
• —升級至 4.11.4-1 或更新版本

CVE-2020-11742 正在被利用嗎?

低 — EPSS 為 0.4%,目前沒有觀察到大規模利用活動。

受影響套件(2)

• from 0, < 4.12.2-r1
• from 0, < 4.11.4-1

CVSS 分數

參考連結(2)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2020-11742
• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2020-11742