CVE-2022-26362
Vulnerability Summary
Timeline
Description
x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.
CVSS Metrics
- v3.1•MEDIUM•Score: 6.4CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
- v2.0•MEDIUM•Score: 6.9AV:L/AC:M/Au:N/C:C/I:C/A:C
EPSS Trends
Current EPSS score: 0.05%• Percentile: 15%
Techniques & Countermeasures
- CWE-362•Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.
Affected Systems
- debian•debian_linux
11.0
- fedoraproject•fedora
35 | 36
References (8)
- https://xenbits.xenproject.org/xsa/advisory-401.txt
- http://xenbits.xen.org/xsa/advisory-401.html
- http://www.openwall.com/lists/oss-security/2022/06/09/3
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OH65U6FTTB5MLH5A6Q3TW7KVCGOG4MYI/
- http://packetstormsecurity.com/files/167718/Xen-TLB-Flush-Bypass.html
- https://www.debian.org/security/2022/dsa-5184
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RKRXZ4LHGCGMOG24ZCEJNY6R2BTS4S2Q/
- https://security.gentoo.org/glsa/202208-23