CVE-2021-26932

medium
New! CVE Severity Now Using CVSS v3

The calculated severity for CVEs has been updated to use CVSS v3 by default. CVEs that do not have a CVSS v3 score will fall back CVSS v2 for calculating severity. Severity display preferences can be toggled in the settings dropdown.

Description

An issue was discovered in the Linux kernel 3.2 through 5.10.16, as used by Xen. Grant mapping operations often occur in batch hypercalls, where a number of operations are done in a single hypercall, the success or failure of each one is reported to the backend driver, and the backend driver then loops over the results, performing follow-up actions based on the success or failure of each operation. Unfortunately, when running in PV mode, the Linux backend drivers mishandle this: Some errors are ignored, effectively implying their success from the success of related batch elements. In other cases, errors resulting from one batch element lead to further batch elements not being inspected, and hence successful ones to not be possible to properly unmap upon error recovery. Only systems with Linux backends running in PV mode are vulnerable. Linux backends run in HVM / PVH modes are not vulnerable. This affects arch/*/xen/p2m.c and drivers/xen/gntdev.c.

References

http://xenbits.xen.org/xsa/advisory-361.html

https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html

https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html

https://lists.fedoraproject.org/archives/list/[email protected]ts.fedoraproject.org/message/2XQR52ICKRK3GC4HDWLMWF2U55YGAR63/

https://lists.fedoraproject.org/archives/list/[email protected]/message/GWQWPWYZRXVFJI5M3VCM72X27IB7CKOB/

https://security.netapp.com/advisory/ntap-20210326-0001/

Details

Source: MITRE

Published: 2021-02-17

Updated: 2021-03-31

Risk Information

CVSS v2

Base Score: 1.9

Vector: AV:L/AC:M/Au:N/C:N/I:N/A:P

Impact Score: 2.9

Exploitability Score: 3.4

Severity: LOW

CVSS v3

Base Score: 5.5

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Impact Score: 3.6

Exploitability Score: 1.8

Severity: MEDIUM

Tenable Plugins

View all (29 total)

IDNameProductFamilySeverity
148700SUSE SLES12 Security Update : kernel (SUSE-SU-2021:1210-1)NessusSuSE Local Security Checks
high
148548Oracle Linux 7 / 8 : Unbreakable Enterprise kernel-container (ELSA-2021-9057)NessusOracle Linux Local Security Checks
high
148546Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2021-9051)NessusOracle Linux Local Security Checks
high
148509SUSE SLES12 Security Update : kernel (SUSE-SU-2021:1175-1)NessusSuSE Local Security Checks
medium
148254Debian DLA-2610-1 : linux-4.19 security updateNessusDebian Local Security Checks
high
148088Oracle Linux 7 : Unbreakable Enterprise kernel-container (ELSA-2021-9136)NessusOracle Linux Local Security Checks
high
148036Oracle Linux 7 : Unbreakable Enterprise kernel (ELSA-2021-9135)NessusOracle Linux Local Security Checks
high
147919Amazon Linux AMI : kernel (ALAS-2021-1487)NessusAmazon Linux Local Security Checks
high
147914Amazon Linux 2 : kernel (ALAS-2021-1616)NessusAmazon Linux Local Security Checks
high
147804Oracle Linux 7 : Unbreakable Enterprise kernel (ELSA-2021-9052)NessusOracle Linux Local Security Checks
high
147597SUSE SLES12 Security Update : kernel (SUSE-SU-2021:0744-1)NessusSuSE Local Security Checks
high
147591SUSE SLES15 Security Update : kernel (SUSE-SU-2021:0735-1)NessusSuSE Local Security Checks
high
147586SUSE SLES15 Security Update : kernel (SUSE-SU-2021:0740-1)NessusSuSE Local Security Checks
high
147579SUSE SLED15 / SLES15 Security Update : kernel (SUSE-SU-2021:0741-1)NessusSuSE Local Security Checks
high
147568SUSE SLES12 Security Update : kernel (SUSE-SU-2021:0736-1)NessusSuSE Local Security Checks
high
147563openSUSE Security Update : the Linux Kernel (openSUSE-2021-393)NessusSuSE Local Security Checks
high
147544SUSE SLES12 Security Update : kernel (SUSE-SU-2021:0743-1)NessusSuSE Local Security Checks
high
147532Debian DLA-2586-1 : linux security updateNessusDebian Local Security Checks
high
147464SUSE SLES15 Security Update : kernel (SUSE-SU-2021:0737-1)NessusSuSE Local Security Checks
high
147204Oracle Linux 7 / 8 : Unbreakable Enterprise kernel (ELSA-2021-9085)NessusOracle Linux Local Security Checks
high
147203Oracle Linux 7 / 8 : Unbreakable Enterprise kernel-container (ELSA-2021-9086)NessusOracle Linux Local Security Checks
high
146993Oracle Linux 6 / 7 : Unbreakable Enterprise kernel (ELSA-2021-9079)NessusOracle Linux Local Security Checks
high
146905Fedora 33 : kernel (2021-7143aca8cb)NessusFedora Local Security Checks
high
146894Fedora 32 : kernel (2021-8d45d297c6)NessusFedora Local Security Checks
high
146833FreeBSD : FreeBSD -- Xen grant mapping error handling issues (5b8c6e1e-770f-11eb-b87a-901b0ef719ab)NessusFreeBSD Local Security Checks
medium
146588Oracle Linux 7 : Unbreakable Enterprise kernel (ELSA-2021-9067)NessusOracle Linux Local Security Checks
high
146587Oracle Linux 7 : Unbreakable Enterprise kernel-container (ELSA-2021-9068)NessusOracle Linux Local Security Checks
high
146549Oracle Linux 7 : Unbreakable Enterprise kernel-container (ELSA-2021-9058)NessusOracle Linux Local Security Checks
high
146534Oracle Linux 7 / 8 : Unbreakable Enterprise kernel (ELSA-2021-9053)NessusOracle Linux Local Security Checks
high