Overview
- Description
- Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, are de-allocated when a guest switches (back) from v2 to v1. Freeing such pages requires that the hypervisor enforce that no parallel request can result in the addition of a mapping of such a page to a guest. That enforcement was missing, allowing guests to retain access to pages that were freed and perhaps re-used for other purposes. Unfortunately, when XSA-379 was being prepared, this similar issue was not noticed.
- Source
- security@xen.org
- NVD status
- Modified
Risk scores
CVSS 3.1
- Type
- Primary
- Base score
- 7.8
- Impact score
- 6
- Exploitability score
- 1.1
- Vector string
- CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
- Severity
- HIGH
CVSS 2.0
- Type
- Primary
- Base score
- 4.4
- Impact score
- 6.4
- Exploitability score
- 3.4
- Vector string
- AV:L/AC:M/Au:N/C:P/I:P/A:P
Weaknesses
- nvd@nist.gov
- CWE-362
Social media
- Hype score
- Not currently trending
Configurations
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