Vulnerability in Xen
CVE-2022-23033
arm: guest_physmap_remove_page not removing the p2m mappings The functions to remove one or more entries from a guest p2m pagetable on Arm (p2m_remove_mapping, guest_physmap_remove_page, and p2m_set_entry with mfn set to INVALID_MFN) do not actually clear the pagetable entry if the entry doesn't have the valid bit set. It is possible to have a valid pagetable entry without the valid bit set when a guest operating system uses set/way cache maintenance instructions. For instance, a guest issuing a set/way cache maintenance instruction, then calling the XENMEM_decrease_reservation hypercall to give back memory pages to Xen, might be able to retain access to those pages even after Xen started reusing them for other purposes.
EPSS: 0.003 (26.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Xen — versions consult Xen advisory XSA-393
- Debian Debian_linux — versions 11.0
- Fedoraproject Fedora — versions 34
Weakness classification (CWE)
References
- security@xen.org (x_refsource_MISC, Vendor Advisory)
- security@xen.org (mailing-list, x_refsource_MLIST, Patch, Mailing List, Third Party Advisory)
- security@xen.org (x_refsource_FEDORA, vendor-advisory)
- security@xen.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
- security@xen.org (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2022-23033?
- CVE-2022-23033 is a high-severity vulnerability in Xen, classified under Improper Resource Shutdown or Release. CVSS score: 7.8/10. Published 2022-01-25.
- How severe is CVE-2022-23033?
- High severity. CVSS v3 base score is 7.8 out of 10.