UBUNTU-CVE-2022-23036: Race Condition

Q: Which systems are exposed to this issue?

Systems using the Linux Xen PV blkfront device frontend are exposed when a malicious backend can interact with the frontend's grant-table mappings. The affected Ubuntu kernel packages listed are linux, linux-aws, linux-azure, linux-gcp, and their listed FIPS variants.

Q: What access does an attacker need to exploit it?

An attacker needs to control or operate a malicious Xen backend for the affected PV block frontend. Exploitation relies on racing the frontend's check of whether a grant reference is in use with the backend mapping the granted page.

Q: What could a successful attack allow?

A malicious backend may retain access to a guest memory page after frontend I/O has completed. This can result in guest data disclosure, data corruption, or denial of service.

Published Mar 10, 2022

Updated

Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backends in ways being subject to race conditions, resulting in potential data leaks, data corruption by malicious backends, and denial of service triggered by malicious backends: blkfront, netfront, scsifront and the gntalloc driver are testing whether a grant reference is still in use. If this is not the case, they assume that a following removal of the granted access will always succeed, which is not true in case the backend has mapped the granted page between those two operations. As a result the backend can keep access to the memory page of the guest no matter how the page will be used after the frontend I/O has finished. The xenbus driver has a similar problem, as it doesn't check the success of removing the granted access of a shared ring buffer. blkfront: CVE-2022-23036 netfront: CVE-2022-23037 scsifront: CVE-2022-23038 gntalloc: CVE-2022-23039 xenbus: CVE-2022-23040 blkfront, netfront, scsifront, usbfront, dmabuf, xenbus, 9p, kbdfront, and pvcalls are using a functionality to delay freeing a grant reference until it is no longer in use, but the freeing of the related data page is not synchronized with dropping the granted access. As a result the backend can keep access to the memory page even after it has been freed and then re-used for a different purpose. CVE-2022-23041 netfront will fail a BUGON() assertion if it fails to revoke access in the rx path. This will result in a Denial of Service (DoS) situation of the guest which can be triggered by the backend. CVE-2022-23042

Affected Software

104 affected componentsFixes available

ubuntu/linux-azure<4.15.0-1138.151~14.04.1

4.15.0-1138.151~14.04.1

ubuntu/linux*

ubuntu/linux-aws*

ubuntu/linux-lts-xenial<4.4.0-291.325~14.04.1

4.4.0-291.325~14.04.1

ubuntu/linux-aws-hwe<4.15.0-1128.137~16.04.1

4.15.0-1128.137~16.04.1

ubuntu/linux-azure<4.15.0-1138.151~16.04.1

4.15.0-1138.151~16.04.1

ubuntu/linux-gcp<4.15.0-1122.136~16.04.1

4.15.0-1122.136~16.04.1

ubuntu/linux-hwe<4.15.0-177.186~16.04.1

4.15.0-177.186~16.04.1

ubuntu/linux-oracle<4.15.0-1093.102~16.04.1

4.15.0-1093.102~16.04.1

ubuntu/linux<4.4.0-291.325

4.4.0-291.325

ubuntu/linux-aws<4.4.0-1200.215

4.4.0-1200.215

ubuntu/linux-hwe-edge*

ubuntu/linux-kvm<4.4.0-1163.174

4.4.0-1163.174

ubuntu/linux-fips*

ubuntu/linux<4.15.0-177.186

4.15.0-177.186

ubuntu/linux-aws<4.15.0-1128.137

4.15.0-1128.137

ubuntu/linux-aws-5.4<5.4.0-1078.84~18.04.1

5.4.0-1078.84~18.04.1

ubuntu/linux-azure-4.15<4.15.0-1138.151

4.15.0-1138.151

ubuntu/linux-azure-5.4<5.4.0-1083.87~18.04.1

5.4.0-1083.87~18.04.1

ubuntu/linux-dell300x<4.15.0-1042.47

4.15.0-1042.47

ubuntu/linux-gcp-4.15<4.15.0-1122.136

4.15.0-1122.136

ubuntu/linux-gcp-5.4<5.4.0-1078.84~18.04.1

5.4.0-1078.84~18.04.1

ubuntu/linux-gke-5.4<5.4.0-1074.79~18.04.1

5.4.0-1074.79~18.04.1

ubuntu/linux-gkeop-5.4<5.4.0-1046.48~18.04.1

5.4.0-1046.48~18.04.1

ubuntu/linux-hwe-5.4<5.4.0-117.132~18.04.1

5.4.0-117.132~18.04.1

ubuntu/linux-ibm-5.4<5.4.0-1028.32~18.04.1

5.4.0-1028.32~18.04.1

ubuntu/linux-kvm<4.15.0-1114.117

4.15.0-1114.117

ubuntu/linux-oracle<4.15.0-1093.102

4.15.0-1093.102

ubuntu/linux-oracle-5.4<5.4.0-1076.83~18.04.1

5.4.0-1076.83~18.04.1

ubuntu/linux-raspi-5.4<5.4.0-1065.75~18.04.1

5.4.0-1065.75~18.04.1

ubuntu/linux-raspi2<4.15.0-1109.116

4.15.0-1109.116

ubuntu/linux-snapdragon<4.15.0-1127.136

4.15.0-1127.136

ubuntu/linux-aws-5.0*

ubuntu/linux-aws-5.3*

ubuntu/linux-azure*

ubuntu/linux-azure-5.3*

ubuntu/linux-azure-edge*

ubuntu/linux-gcp*

ubuntu/linux-gcp-5.3*

ubuntu/linux-gke-4.15*

ubuntu/linux-hwe*

ubuntu/linux-hwe-edge*

ubuntu/linux-oem*

ubuntu/linux-oracle-5.0*

ubuntu/linux-oracle-5.3*

ubuntu/linux-aws-fips<4.15.0-2067.70

4.15.0-2067.70

ubuntu/linux-azure-fips<4.15.0-2049.53

4.15.0-2049.53

ubuntu/linux-fips<4.15.0-1085.94

4.15.0-1085.94

ubuntu/linux-gcp-fips<4.15.0-2032.35

4.15.0-2032.35

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux<5.4.0-117.132

5.4.0-117.132

ubuntu/linux-aws<5.4.0-1078.84

5.4.0-1078.84

ubuntu/linux-azure<5.4.0-1083.87

5.4.0-1083.87

ubuntu/linux-bluefield<5.4.0-1040.44

5.4.0-1040.44

ubuntu/linux-gcp<5.4.0-1078.84

5.4.0-1078.84

ubuntu/linux-gke<5.4.0-1074.79

5.4.0-1074.79

ubuntu/linux-gkeop<5.4.0-1046.48

5.4.0-1046.48

ubuntu/linux-ibm<5.4.0-1026.29

5.4.0-1026.29

ubuntu/linux-intel-iotg-5.15<5.15.0-1008.11~20.04.1

5.15.0-1008.11~20.04.1

ubuntu/linux-iot<5.4.0-1004.6

5.4.0-1004.6

ubuntu/linux-kvm<5.4.0-1068.72

5.4.0-1068.72

ubuntu/linux-oracle<5.4.0-1076.83

5.4.0-1076.83

ubuntu/linux-raspi<5.4.0-1065.75

5.4.0-1065.75

ubuntu/linux-aws-5.11*

ubuntu/linux-aws-5.13*

ubuntu/linux-aws-5.8*

ubuntu/linux-azure-5.11*

ubuntu/linux-azure-5.13*

ubuntu/linux-azure-5.8*

ubuntu/linux-azure-fde-5.15<5.15.0-1114.123~20.04.1

5.15.0-1114.123~20.04.1

ubuntu/linux-gcp-5.11*

ubuntu/linux-gcp-5.13*

ubuntu/linux-gcp-5.8*

ubuntu/linux-hwe-5.11*

ubuntu/linux-hwe-5.13*

ubuntu/linux-hwe-5.8*

ubuntu/linux-intel-5.13*

ubuntu/linux-oem-5.10*

ubuntu/linux-oem-5.13*

ubuntu/linux-oem-5.6*

ubuntu/linux-oracle-5.11*

ubuntu/linux-oracle-5.13*

ubuntu/linux-oracle-5.8*

ubuntu/linux-raspi2*

ubuntu/linux-riscv*

ubuntu/linux-riscv-5.11*

ubuntu/linux-riscv-5.8*

ubuntu/linux-aws-fips<5.4.0-1078.84+fips1

5.4.0-1078.84+fips1

ubuntu/linux-azure-fips<5.4.0-1083.87+fips1

5.4.0-1083.87+fips1

ubuntu/linux-fips<5.4.0-1054.61

5.4.0-1054.61

ubuntu/linux-gcp-fips<5.4.0-1078.84+fips1

5.4.0-1078.84+fips1

ubuntu/linux-aws-fips*

ubuntu/linux-azure-fips*

ubuntu/linux-fips*

ubuntu/linux-gcp-fips*

ubuntu/linux-intel-iot-realtime*

ubuntu/linux-realtime*

ubuntu/linux-realtime<5.15.0-1007.7

5.15.0-1007.7

ubuntu/linux-raspi-realtime*

ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1138.151~14.04.1
Upgrade
Upgrade ubuntu/linux-lts-xenial to a version that resolves this vulnerability.
Fixed in 4.4.0-291.325~14.04.1
Upgrade
Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-1128.137~16.04.1
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 4.15.0-1138.151~16.04.1
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 4.15.0-1122.136~16.04.1
Upgrade
Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.
Fixed in 4.15.0-177.186~16.04.1
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1093.102~16.04.1
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 4.4.0-291.325
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.4.0-1200.215
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 4.4.0-1163.174
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 4.15.0-177.186
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 4.15.0-1128.137
Upgrade
Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84~18.04.1
Upgrade
Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1138.151
Upgrade
Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1083.87~18.04.1
Upgrade
Upgrade ubuntu/linux-dell300x to a version that resolves this vulnerability.
Fixed in 4.15.0-1042.47
Upgrade
Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.
Fixed in 4.15.0-1122.136
Upgrade
Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84~18.04.1
Upgrade
Upgrade ubuntu/linux-gke-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1074.79~18.04.1
Upgrade
Upgrade ubuntu/linux-gkeop-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1046.48~18.04.1
Upgrade
Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-117.132~18.04.1
Upgrade
Upgrade ubuntu/linux-ibm-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1028.32~18.04.1
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 4.15.0-1114.117
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 4.15.0-1093.102
Upgrade
Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1076.83~18.04.1
Upgrade
Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.
Fixed in 5.4.0-1065.75~18.04.1
Upgrade
Upgrade ubuntu/linux-raspi2 to a version that resolves this vulnerability.
Fixed in 4.15.0-1109.116
Upgrade
Upgrade ubuntu/linux-snapdragon to a version that resolves this vulnerability.
Fixed in 4.15.0-1127.136
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2067.70
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2049.53
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-1085.94
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 4.15.0-2032.35
Upgrade
Upgrade ubuntu/linux to a version that resolves this vulnerability.
Fixed in 5.4.0-117.132
Upgrade
Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84
Upgrade
Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.
Fixed in 5.4.0-1083.87
Upgrade
Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.
Fixed in 5.4.0-1040.44
Upgrade
Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84
Upgrade
Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.
Fixed in 5.4.0-1074.79
Upgrade
Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.
Fixed in 5.4.0-1046.48
Upgrade
Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.
Fixed in 5.4.0-1026.29
Upgrade
Upgrade ubuntu/linux-intel-iotg-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1008.11~20.04.1
Upgrade
Upgrade ubuntu/linux-iot to a version that resolves this vulnerability.
Fixed in 5.4.0-1004.6
Upgrade
Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.
Fixed in 5.4.0-1068.72
Upgrade
Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.
Fixed in 5.4.0-1076.83
Upgrade
Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.
Fixed in 5.4.0-1065.75
Upgrade
Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.
Fixed in 5.15.0-1114.123~20.04.1
Upgrade
Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84+fips1
Upgrade
Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1083.87+fips1
Upgrade
Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1054.61
Upgrade
Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.
Fixed in 5.4.0-1078.84+fips1
Upgrade
Upgrade ubuntu/linux-realtime to a version that resolves this vulnerability.
Fixed in 5.15.0-1007.7

Event History

Mar 10, 2022

CVE Published

via OSV·08:15 PM

Data Sourced

via OSV·08:15 PM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which systems are exposed to this issue?

Systems using the Linux Xen PV blkfront device frontend are exposed when a malicious backend can interact with the frontend's grant-table mappings. The affected Ubuntu kernel packages listed are linux, linux-aws, linux-azure, linux-gcp, and their listed FIPS variants.

What access does an attacker need to exploit it?

An attacker needs to control or operate a malicious Xen backend for the affected PV block frontend. Exploitation relies on racing the frontend's check of whether a grant reference is in use with the backend mapping the granted page.

What could a successful attack allow?

A malicious backend may retain access to a guest memory page after frontend I/O has completed. This can result in guest data disclosure, data corruption, or denial of service.

UBUNTU-CVE-2022-23036: Race Condition

Affected Software

Remediation

Event History

Frequently Asked Questions

Which systems are exposed to this issue?

What access does an attacker need to exploit it?

What could a successful attack allow?

Company

Resources

Contact

Frequently Asked Questions

Which systems are exposed to this issue?

What access does an attacker need to exploit it?

What could a successful attack allow?