Xen p2m Mapping guest_physmap_remove_page memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as critical, has been found in Xen (Virtualization Software) (unknown version). This issue affects the function guest_physmap_remove_page of the component p2m Mapping Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was disclosed 01/25/2022. It is possible to read the advisory at xenbits.xenproject.org. The identification of this vulnerability is CVE-2022-23033 since 01/10/2022. The exploitation is known to be difficult. Access to the local network is required for this attack. The requirement for exploitation is a simple authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/28/2022).

Applying a patch is able to eliminate this problem.




CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 4.6
VulDB Meta Temp Score: 4.4

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔒
VulDB Reliability: 🔍



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Memory corruption
CWE: CWE-119
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: xenbits.xenproject.org


01/10/2022 CVE reserved
01/25/2022 +15 days Advisory disclosed
01/25/2022 +0 days VulDB entry created
01/28/2022 +3 days VulDB last update


Advisory: xenbits.xenproject.org
Status: Confirmed

CVE: CVE-2022-23033 (🔒)


Created: 01/25/2022 05:26 PM
Updated: 01/28/2022 11:37 AM
Changes: (1) source_cve_nvd_summary
Complete: 🔍


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