Overview
- Description
- 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.
- Source
- security@xen.org
- NVD status
- Modified
Risk scores
CVSS 3.1
- Type
- Primary
- Base score
- 6.4
- Impact score
- 5.9
- Exploitability score
- 0.5
- Vector string
- CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
- Severity
- MEDIUM
CVSS 2.0
- Type
- Primary
- Base score
- 6.9
- Impact score
- 10
- Exploitability score
- 3.4
- Vector string
- AV:L/AC:M/Au:N/C:C/I:C/A:C
Weaknesses
- nvd@nist.gov
- CWE-362
Social media
- Hype score
- Not currently trending
Configurations
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