Host crash via grant-status frame array overflow
Published Aug 27, 2021 · Updated Aug 3, 2024
Out-of-bounds write in Xen Hypervisor 4.10 and later allows guest OS users to crash the host through a grant-table-v2 request. In the 32-to-64-bit translation for GNTTABOP_get_status_frames, the core routine accepts a capacity scaled eightfold and writes excess frame numbers beyond the translation buffer. Exploitation requires a 32-bit x86 guest kernel allowed to use grant table version 2 and at least 8,177 grant-table frames; privilege escalation and disclosure remain unconfirmed.
Summary
What happened
Out-of-bounds write in Xen Hypervisor 4.10 and later allows guest OS users to crash the host through a grant-table-v2 request. In the 32-to-64-bit translation for GNTTABOP_get_status_frames, the core routine accepts a capacity scaled eightfold and writes excess frame numbers beyond the translation buffer. Exploitation requires a 32-bit x86 guest kernel allowed to use grant table version 2 and at least 8,177 grant-table frames; privilege escalation and disclosure remain unconfirmed.
The record
- CVE
- CVE-2021-28699
- Published
- Aug 27, 2021
- Updated
- Aug 3, 2024
- Vendor
- Xen Project
- Product
- Xen Hypervisor
- Classifications
- T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 27, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=4.11.x <unspecified
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
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Your stack
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