CVE-2022-26356

Description

Racy interactions between dirty vram tracking and paging log dirty hypercalls Activation of log dirty mode done by XEN_DMOP_track_dirty_vram (was named HVMOP_track_dirty_vram before Xen 4.9) is racy with ongoing log dirty hypercalls. A suitably timed call to XEN_DMOP_track_dirty_vram can enable log dirty while another CPU is still in the process of tearing down the structures related to a previously enabled log dirty mode (XEN_DOMCTL_SHADOW_OP_OFF). This is due to lack of mutually exclusive locking between both operations and can lead to entries being added in already freed slots, resulting in a memory leak.

How to fix CVE-2022-26356

To remediate CVE-2022-26356, upgrade the affected package to a fixed version below.

• —upgrade to 4.13.4-r3 or later
• —upgrade to 4.14.4+74-gd7b22226b5-1 or later

Is CVE-2022-26356 being exploited?

Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 4.13.4-r3
• from 0, < 4.14.4+74-gd7b22226b5-1

CVSS scores

References (2)

• ADVISORYsecurity.alpinelinux.org/vuln/CVE-2022-26356
• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2022-26356