Vulnerability in Xen
CVE-2022-26356
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.6 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.002 (13.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 14th percentile — 13.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Xen — versions consult Xen advisory XSA-397
- Debian Linux — versions 11.0
- Fedoraproject Fedora — versions 34, 35
Weakness classification (CWE)
References
- xenbits.xenproject.org/xsa/advisory-397.txt (Third Party Advisory)
- xenbits.xen.org/xsa/advisory-397.html (Patch, Third Party Advisory)
- www.openwall.com/lists/oss-security/2022/04/05/1 (mailing-list, Patch, Mailing List, Third Party Advisory)
- www.debian.org/security/2022/dsa-5117 (vendor-advisory, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- security.gentoo.org/glsa/202402-07 (vendor-advisory)
Frequently asked questions
- What is CVE-2022-26356?
- CVE-2022-26356 is a medium-severity vulnerability in Xen, classified under Improper Locking. CVSS score: 5.6/10. Published 2022-04-05.
- How severe is CVE-2022-26356?
- Medium severity. CVSS v3 base score is 5.6 out of 10.