- Description
- 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.
- Source
- security@xen.org
- NVD status
- Modified
CVSS 3.1
- Type
- Primary
- Base score
- 7.8
- Impact score
- 5.9
- Exploitability score
- 1.8
- Vector string
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Severity
- HIGH
CVSS 2.0
- Type
- Primary
- Base score
- 4.6
- Impact score
- 6.4
- Exploitability score
- 3.9
- Vector string
- AV:L/AC:L/Au:N/C:P/I:P/A:P
- nvd@nist.gov
- CWE-404
- Hype score
- Not currently trending
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