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CVE-2021-21284

privilege escalation in Moby

Published: Feb 2, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-22
NVD MITRE
6.8CVSSMEDIUM
EPSS Score
1.1%
Top 39.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

In Docker before versions 9.03.15, 20.10.3 there is a vulnerability involving the --userns-remap option in which access to remapped root allows privilege escalation to real root. When using "--userns-remap", if the root user in the remapped namespace has access to the host filesystem they can modify files under "/var/lib/docker/<remapping>" that cause writing files with extended privileges. Versions 20.10.3 and 19.03.15 contain patches that prevent privilege escalation from remapped user.

CVSS Vector Breakdown

AV:AAC:LPR:LUI:NS:CC:NI:HA:N
Exploitability
AV:AAttack Vector
Adjacent
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-22

Affected Products

mobymoby
On-prem
Cloud & SaaS / container-orchestration
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
DockerDocker Inc.
On-premDev Tool
Cloud & SaaS / container-orchestration
Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
ОСОН ОСнова ОnyxАО «НППКТ»
On-premOS
Operating Systems / linux-distro
mobyoss-projectCloud & SaaSaka docker moby
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
docker inc.commercialUSCloud & SaaSaka docker
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
ао «нппкт»commercialRUOperating Systems
and 5 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://docs.docker.com/engine/release-notes/#20103
docs.docker.com
https://github.com/moby/moby/releases/tag/v20.10.3
github.com
https://github.com/moby/moby/releases/tag/v19.03.15
github.com
and 15 more references View all →

Timeline

Published
Feb 2, 2021
Last Updated
Nov 21, 2024

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