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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
6.8MEDIUM
NVD MITRE
EPSS Score
1.1%
Top 38.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

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
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Weaknesses

CWE-22

Affected Products

docker
commercial·US
dockerOn-premDev Tool
Cloud & SaaS / container-orchestration
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
netapp
commercial·US
e-series santricity os controller
Hardware Firmware
Сообщество свободного программного обеспечения
oss-projectaka fsf
Debian GNU/LinuxOn-premOS
Operating Systems / linux-distro
Docker Inc.
commercial·USaka docker
DockerOn-premDev Tool
Cloud & SaaS / container-orchestration
ООО «РусБИТех-Астра»
commercial·RUaka rusbitech-astra
Astra Linux Special EditionOn-premOS
Operating Systems / linux-distro
and 4 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

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/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c
github.com
https://github.com/moby/moby/releases/tag/v19.03.15
github.com
and 15 more references View all →

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