CVE-2021-21284

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Source
https://cve.org/CVERecord?id=CVE-2021-21284
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-21284.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-21284
Aliases
Downstream
Related
Published
2021-02-02T18:15:11.827Z
Modified
2026-03-14T14:50:34.661251Z
Severity
  • 6.8 (Medium) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N CVSS Calculator
Summary
[none]
Details

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.

References

Affected packages

Git / github.com/docker/docker

Affected ranges

Type
GIT
Repo
https://github.com/docker/docker
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
420b1d36250f9cfdc561f086f25a213ecb669b6f
Database specific 
{
    "versions": [
        {
            "introduced": "0"
        },
        {
            "fixed": "19.03.15"
        }
    ]
}
Type
GIT
Repo
https://github.com/moby/moby
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
64bd4485b3a66a597c02c95f5776395e540b2c7c
Fixed
420b1d36250f9cfdc561f086f25a213ecb669b6f
Fixed
46229ca1d815cfd4b50eb377ac75ad8300e13a85

Affected versions

0.*
0.0.3
Other
autorun/1
docs-v1.*
docs-v1.12.0-rc4-2016-07-15
upstream/0.*
upstream/0.1.1
upstream/0.1.2
upstream/0.1.3
upstream/0.1.4
v0.*
v0.1.0
v0.1.1
v0.1.2
v0.1.3
v0.1.4
v0.1.5
v0.1.6
v0.1.7
v0.1.8
v0.10.0
v0.11.0
v0.11.1
v0.12.0
v0.2.0
v0.2.1
v0.2.2
v0.3.0
v0.3.1
v0.3.2
v0.3.3
v0.3.4
v0.4.0
v0.4.1
v0.4.2
v0.4.3
v0.4.4
v0.4.5
v0.4.6
v0.4.7
v0.4.8
v0.5.0
v0.5.1
v0.5.2
v0.5.3
v0.6.0
v0.6.1
v0.6.2
v0.6.3
v0.6.4
v0.6.5
v0.6.6
v0.6.7
v0.7.0
v0.7.0-rc5
v0.7.0-rc6
v0.7.1
v0.7.2
v0.7.3
v0.7.4
v0.7.5
v0.7.6
v0.8.0
v0.8.1
v0.9.0
v1.*
v1.0.0
v1.0.1
v1.1.0
v1.1.1
v1.1.2
v1.2.0
v1.3.0
v1.3.1
v1.3.2
v1.3.3
v1.4.0
v1.4.1
v17.*
v17.12.0-ce-rc1
v18.*
v18.04.0-ce-rc1
v18.06.0-ce-rc1
v18.09.0-ce-tp0
v19.*
v19.03.0
v19.03.0-beta1
v19.03.0-beta2
v19.03.0-beta3
v19.03.0-beta4
v19.03.0-beta5
v19.03.0-rc2
v19.03.0-rc3
v19.03.1
v19.03.10
v19.03.11
v19.03.12
v19.03.13
v19.03.13-beta1
v19.03.13-beta2
v19.03.14
v19.03.2
v19.03.2-beta1
v19.03.2-rc1
v19.03.3
v19.03.3-beta1
v19.03.3-beta2
v19.03.3-rc1
v19.03.4
v19.03.4-rc1
v19.03.5
v19.03.5-beta1
v19.03.5-beta2
v19.03.5-rc1
v19.03.6
v19.03.6-rc1
v19.03.6-rc2
v19.03.7
v19.03.8
v19.03.9
v20.*
v20.10.0
v20.10.0-beta1
v20.10.0-rc1
v20.10.0-rc2
v20.10.1
v20.10.2

Database specific

unresolved_ranges 
[
    {
        "events": [
            {
                "introduced": "20.0.0"
            },
            {
                "fixed": "20.10.3"
            }
        ]
    },
    {
        "events": [
            {
                "introduced": "0"
            },
            {
                "last_affected": "10.0"
            }
        ]
    },
    {
        "events": [
            {
                "introduced": "11.0.0"
            },
            {
                "last_affected": "11.60.3"
            }
        ]
    }
]
source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-21284.json"