An issue was discovered in Xen through 4.14.x. A bounds check common to most operation time functions specific to FIFO event channels depends on the CPU observing consistent state. While the producer side uses appropriately ordered writes, the consumer side isn't protected against re-ordered reads, and may hence end up de-referencing a NULL pointer. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system. Only Arm systems may be vulnerable. Whether a system is vulnerable depends on the specific CPU. x86 systems are not vulnerable.
Metrics
Affected Vendors & Products
Advisories
Source | ID | Title |
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DSA-4812-1 | xen security update |
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EUVD-2020-21933 | An issue was discovered in Xen through 4.14.x. A bounds check common to most operation time functions specific to FIFO event channels depends on the CPU observing consistent state. While the producer side uses appropriately ordered writes, the consumer side isn't protected against re-ordered reads, and may hence end up de-referencing a NULL pointer. Malicious or buggy guest kernels can mount a Denial of Service (DoS) attack affecting the entire system. Only Arm systems may be vulnerable. Whether a system is vulnerable depends on the specific CPU. x86 systems are not vulnerable. |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
No history.

Status: PUBLISHED
Assigner: mitre
Published:
Updated: 2024-08-04T16:55:10.337Z
Reserved: 2020-12-04T00:00:00
Link: CVE-2020-29571

No data.

Status : Modified
Published: 2020-12-15T17:15:14.817
Modified: 2024-11-21T05:24:13.790
Link: CVE-2020-29571

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