CVE-2022-26362
x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count.…
- Published
- Updated
- Reserved
- Assigned by
- XEN
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.
Timeline
ID reserved
By XEN
- 3 months later
· 3 months later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium6.4 | CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.39% · top 67% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.4.
Weakness
Affected products
References (8)
- https://xenbits.xenproject.org/xsa/advisory-401.txt (opens in a new tab)x_refsource_MISCx_transferred
- http://xenbits.xen.org/xsa/advisory-401.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- [oss-security] 20220609 Xen Security Advisory 401 v2 (CVE-2022-26362) - x86 pv: Race condition in typeref acquisition (opens in a new tab)mailing-listx_refsource_MLISTx_transferred
- FEDORA-2022-0142d562ca (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- http://packetstormsecurity.com/files/167718/Xen-TLB-Flush-Bypass.html (opens in a new tab)x_refsource_MISCx_transferred
- DSA-5184 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- FEDORA-2022-2c9f8224f8 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- GLSA-202208-23 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2022-26362)Record last updated .