CVE-2022-33745
insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- EPSS
- 0.30% probability · 23th percentile
- CISA KEV
- Not listed
- Affected
- xen/xen · debian/debian linux · fedoraproject/fedora
- Source
- security@xen.org
References
- http://www.openwall.com/lists/oss-security/2022/07/26/2Mailing List, Patch, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2022/07/26/3Mailing List, Patch, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-408.htmlPatch, Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HUFIMNGYP5VQAA6KE3T2I5GW6UP6F7BS/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MYI3OMJ7RIZNL3C6GUWNANNPEUUID6FM/
- https://www.debian.org/security/2022/dsa-5272Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-408.txtVendor Advisory
- http://www.openwall.com/lists/oss-security/2022/07/26/2Mailing List, Patch, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2022/07/26/3Mailing List, Patch, Third Party Advisory
- http://xenbits.xen.org/xsa/advisory-408.htmlPatch, Vendor Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HUFIMNGYP5VQAA6KE3T2I5GW6UP6F7BS/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MYI3OMJ7RIZNL3C6GUWNANNPEUUID6FM/
- https://www.debian.org/security/2022/dsa-5272Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-408.txtVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.