CVE-2022-26362

x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.

• CVE ID
• CVE-2022-26362

• Assigner
• security@xen.org

• Vulnerability Status
• Analyzed

• Published Version
• 2022-06-09T17:15:08

• Last Modified Date
• 2022-08-24T18:35:05

• Version
• 2.0

• Vector String
• AV:L/AC:M/Au:N/C:C/I:C/A:C

• Access Vector
• LOCAL

• Access Compatibility
• MEDIUM

• Authentication
• NONE

• Confidentiality Impact
• COMPLETE

• Integrity Impact
• COMPLETE

• Availability Impact
• COMPLETE

• Base Score
• 6.9

• Severity
• MEDIUM

• Exploitability Score
• 3.4

• Impact Score
• 10

• Version
• 3.1

• Vector String
• CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

• Attack Vector
• LOCAL

• Attack Compatibility
• HIGH

• Privileges Required
• HIGH

• User Interaction
• NONE

• Scope
• UNCHANGED

• Confidentiality Impact
• HIGH

• Availability Impact
• HIGH

• Base Score
• 6.4

• Base Severity
• MEDIUM

• Exploitability Score
• 0.5

• Impact Score
• 5.9