CVE-2020-28374
Publication date 12 January 2021
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
In drivers/target/target_core_xcopy.c in the Linux kernel before 5.10.7, insufficient identifier checking in the LIO SCSI target code can be used by remote attackers to read or write files via directory traversal in an XCOPY request, aka CID-2896c93811e3. For example, an attack can occur over a network if the attacker has access to one iSCSI LUN. The attacker gains control over file access because I/O operations are proxied via an attacker-selected backstore.
From the Ubuntu Security Team
It was discovered that the LIO SCSI target implementation in the Linux kernel performed insufficient identifier checking in certain XCOPY requests. An attacker with access to at least one LUN in a multiple backstore environment could use this to expose sensitive information or modify data.
Mitigation
XCOPY support is enabled by default, but can be disabled via: echo 0 > /sys/kernel/config/target/core/<backstore>/<name>/attrib/emulate_3pc or targetcli /backstores/<backstore>/<name> set attribute emulate_3pc=0 . This workaround does *not* affect XCOPY requests sent to tcmu-runner based backstores.
Status
Package | Ubuntu Release | Status |
---|---|---|
linux | ||
20.04 LTS focal |
Fixed 5.4.0-62.70
|
|
18.04 LTS bionic |
Fixed 4.15.0-132.136
|
|
16.04 LTS xenial |
Fixed 4.4.0-200.232
|
|
14.04 LTS trusty |
Fixed 3.13.0-184.235
|
|
linux-aws | ||
20.04 LTS focal |
Fixed 5.4.0-1037.39
|
|
18.04 LTS bionic |
Fixed 4.15.0-1093.99
|
|
16.04 LTS xenial |
Fixed 4.4.0-1121.135
|
|
14.04 LTS trusty |
Fixed 4.4.0-1085.89
|
|
linux-aws-5.0 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-aws-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-aws-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1037.39~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-aws-hwe | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Not in release | |
16.04 LTS xenial |
Fixed 4.15.0-1093.99~16.04.1
|
|
14.04 LTS trusty | Not in release | |
linux-azure | ||
20.04 LTS focal |
Fixed 5.4.0-1039.41
|
|
18.04 LTS bionic | Ignored | |
16.04 LTS xenial |
Fixed 4.15.0-1106.118~16.04.1
|
|
14.04 LTS trusty |
Fixed 4.15.0-1106.118~14.04.1
|
|
linux-azure-4.15 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 4.15.0-1106.118
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-azure-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-azure-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1039.41~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-azure-edge | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-dell300x | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 4.15.0-1011.15
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gcp | ||
20.04 LTS focal |
Fixed 5.4.0-1036.39
|
|
18.04 LTS bionic | Ignored | |
16.04 LTS xenial |
Fixed 4.15.0-1092.105~16.04.1
|
|
14.04 LTS trusty | Not in release | |
linux-gcp-4.15 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 4.15.0-1092.105
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gcp-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gcp-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1036.39~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gcp-edge | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gke-4.15 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 4.15.0-1078.83
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gke-5.0 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.0.0-1051.53
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gke-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.3.0-1040.43
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gke-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1035.37~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gkeop | ||
20.04 LTS focal |
Fixed 5.4.0-1009.10
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-gkeop-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1009.10~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-hwe | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.3.0-70.66
|
|
16.04 LTS xenial |
Fixed 4.15.0-132.136~16.04.1
|
|
14.04 LTS trusty | Not in release | |
linux-hwe-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-62.70~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-hwe-5.8 | ||
20.04 LTS focal |
Fixed 5.8.0-38.43~20.04.1
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-hwe-edge | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Ignored | |
14.04 LTS trusty | Not in release | |
linux-kvm | ||
20.04 LTS focal |
Fixed 5.4.0-1032.33
|
|
18.04 LTS bionic |
Fixed 4.15.0-1084.86
|
|
16.04 LTS xenial |
Fixed 4.4.0-1087.96
|
|
14.04 LTS trusty | Not in release | |
linux-lts-trusty | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-lts-xenial | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty |
Fixed 4.4.0-200.232~14.04.1
|
|
linux-oem | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Ignored | |
14.04 LTS trusty | Not in release | |
linux-oem-5.10 | ||
20.04 LTS focal |
Fixed 5.10.0-1014.15
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-oem-5.6 | ||
20.04 LTS focal |
Fixed 5.6.0-1047.51
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-oem-osp1 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-oracle | ||
20.04 LTS focal |
Fixed 5.4.0-1037.40
|
|
18.04 LTS bionic |
Fixed 4.15.0-1064.71
|
|
16.04 LTS xenial |
Fixed 4.15.0-1064.71~16.04.1
|
|
14.04 LTS trusty | Not in release | |
linux-oracle-5.0 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-oracle-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic | Ignored | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-oracle-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1037.40~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-raspi | ||
20.04 LTS focal |
Fixed 5.4.0-1028.31
|
|
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-raspi-5.4 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.4.0-1028.31~18.04.1
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-raspi2 | ||
20.04 LTS focal | Ignored | |
18.04 LTS bionic |
Fixed 4.15.0-1078.83
|
|
16.04 LTS xenial |
Fixed 4.4.0-1145.155
|
|
14.04 LTS trusty | Not in release | |
linux-raspi2-5.3 | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 5.3.0-1037.39
|
|
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-riscv | ||
20.04 LTS focal | Ignored | |
18.04 LTS bionic | Not in release | |
16.04 LTS xenial | Not in release | |
14.04 LTS trusty | Not in release | |
linux-snapdragon | ||
20.04 LTS focal | Not in release | |
18.04 LTS bionic |
Fixed 4.15.0-1095.104
|
|
16.04 LTS xenial |
Fixed 4.4.0-1149.159
|
|
14.04 LTS trusty | Not in release |
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sbeattie
MITIGATION XCOPY support is enabled by default, but can be disabled via: echo 0 > /sys/kernel/config/target/core/<backstore>/<name>/attrib/emulate_3pc or targetcli /backstores/<backstore>/<name> set attribute emulate_3pc=0 . This workaround does *not* affect XCOPY requests sent to tcmu-runner based backstores.
Severity score breakdown
Parameter | Value |
---|---|
Base score | 8.1 · High |
Attack vector | Network |
Attack complexity | Low |
Privileges required | Low |
User interaction | None |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | High |
Availability impact | None |
Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N |
References
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