Vulnerabilities > CVE-2021-26933
Attack vector
LOCAL Attack complexity
LOW Privileges required
LOW Confidentiality impact
HIGH Integrity impact
NONE Availability impact
NONE Summary
An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortunately, the operation to clean the cache is happening before checking if the page was scrubbed. Therefore there is no guarantee when all the writes will reach the memory.
Vulnerable Configurations
Part | Description | Count |
---|---|---|
OS | Xen
| 23 |
OS | 2 | |
OS | 1 |
References
- http://xenbits.xen.org/xsa/advisory-364.html
- https://www.debian.org/security/2021/dsa-4888
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4GELN5E6MDR5KQBJF5M5COUUED3YFZTD/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EOAJBVAVR6RSCUCHNXPVSNRPSFM7INMP/