CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:L/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
EPSS
Percentile
27.5%
Rogue backends can cause DoS of guests via high frequency events T[his CNA
information record relates to multiple CVEs; the text explains which
aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to
run PV backends in regular unprivileged guests, typically referred to as
“driver domains”. Running PV backends in driver domains has one primary
security advantage: if a driver domain gets compromised, it doesn’t have
the privileges to take over the system. However, a malicious driver domain
could try to attack other guests via sending events at a high frequency
leading to a Denial of Service in the guest due to trying to service
interrupts for elongated amounts of time. There are three affected
backends: * blkfront patch 1, CVE-2021-28711 * netfront patch 2,
CVE-2021-28712 * hvc_xen (console) patch 3, CVE-2021-28713
Author | Note |
---|---|
rodrigo-zaiden | linux-aws in 4.4 kernels (trusty and xenial) won’t include fixes for this CVE as these kernels may have xen/blkfront specific changes and the backport is too risky. |
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 18.04 | noarch | linux | < 4.15.0-169.177 | UNKNOWN |
ubuntu | 20.04 | noarch | linux | < 5.4.0-105.119 | UNKNOWN |
ubuntu | 21.10 | noarch | linux | < 5.13.0-37.42 | UNKNOWN |
ubuntu | 16.04 | noarch | linux | < 4.4.0-239.273 | UNKNOWN |
ubuntu | 18.04 | noarch | linux-aws | < 4.15.0-1121.129 | UNKNOWN |
ubuntu | 20.04 | noarch | linux-aws | < 5.4.0-1069.73 | UNKNOWN |
ubuntu | 21.10 | noarch | linux-aws | < 5.13.0-1019.21 | UNKNOWN |
ubuntu | 20.04 | noarch | linux-aws-5.13 | < 5.13.0-1019.21~20.04.1 | UNKNOWN |
ubuntu | 18.04 | noarch | linux-aws-5.4 | < 5.4.0-1069.73~18.04.1 | UNKNOWN |
ubuntu | 16.04 | noarch | linux-aws-hwe | < 4.15.0-1120.128~16.04.1 | UNKNOWN |
launchpad.net/bugs/cve/CVE-2021-28711
nvd.nist.gov/vuln/detail/CVE-2021-28711
security-tracker.debian.org/tracker/CVE-2021-28711
ubuntu.com/security/notices/USN-5298-1
ubuntu.com/security/notices/USN-5337-1
ubuntu.com/security/notices/USN-5338-1
ubuntu.com/security/notices/USN-5368-1
ubuntu.com/security/notices/USN-5377-1
ubuntu.com/security/notices/USN-6014-1
www.cve.org/CVERecord?id=CVE-2021-28711
xenbits.xen.org/xsa/advisory-391.html
CVSS2
Attack Vector
LOCAL
Attack Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:L/AC:L/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
EPSS
Percentile
27.5%