An issue was discovered in Xen through 4.11.x allowing x86 PV guest OS users to cause a denial of service by leveraging a long-running operation that exists to support restartability of PTE updates.
The product utilizes multiple threads or processes to allow temporary access to a shared resource that can only be exclusive to one process at a time, but it does not properly synchronize these actions, which might cause simultaneous accesses of this resource by multiple threads or processes.
| Link | Tags |
|---|---|
| http://xenbits.xen.org/xsa/advisory-290.html | vendor advisory |
| https://xenbits.xen.org/xsa/advisory-290.html | patch vendor advisory mitigation |
| http://www.openwall.com/lists/oss-security/2019/10/25/3 | third party advisory mailing list |
| https://www.debian.org/security/2020/dsa-4602 | third party advisory vendor advisory |
| https://seclists.org/bugtraq/2020/Jan/21 | third party advisory mailing list |