CVE-2021-21284
Docker RCE through User Namespace Remapping
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.
INFO
Published Date :
Feb. 2, 2021, 6:15 p.m.
Last Modified :
April 29, 2022, 7:22 p.m.
Source :
[email protected]
Remotely Exploitable :
No
Impact Score :
4.0
Exploitability Score :
2.3
Public PoC/Exploit Available at Github
CVE-2021-21284 has a 2 public PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
Affected Products
The following products are affected by CVE-2021-21284
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-21284.
| URL | Resource |
|---|---|
| https://docs.docker.com/engine/release-notes/#20103 | Release Notes Vendor Advisory |
| https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c | Patch Third Party Advisory |
| https://github.com/moby/moby/releases/tag/v19.03.15 | Release Notes Third Party Advisory |
| https://github.com/moby/moby/releases/tag/v20.10.3 | Release Notes Third Party Advisory |
| https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc | Third Party Advisory |
| https://security.gentoo.org/glsa/202107-23 | Patch Third Party Advisory |
| https://security.netapp.com/advisory/ntap-20210226-0005/ | Third Party Advisory |
| https://www.debian.org/security/2021/dsa-4865 | Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
⚙ DevSecOps Kubernetes Playground ("A Hacker's Guide to Kubernetes")
Dockerfile Shell Ruby Smarty Jinja HCL
Underground Nexus Deployment - Dockerhub page - https://hub.docker.com/r/phoenixvlabs/core-nexus
Dockerfile Shell CUE
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-21284 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-21284 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Modified Analysis by [email protected]
Apr. 29, 2022
Action Type Old Value New Value Changed Reference Type https://security.gentoo.org/glsa/202107-23 No Types Assigned https://security.gentoo.org/glsa/202107-23 Patch, Third Party Advisory Added CWE NIST CWE-22 -
CVE Modified by [email protected]
Jul. 10, 2021
Action Type Old Value New Value Added Reference https://security.gentoo.org/glsa/202107-23 [No Types Assigned] -
Modified Analysis by [email protected]
Mar. 15, 2021
Action Type Old Value New Value Changed Reference Type https://security.netapp.com/advisory/ntap-20210226-0005/ No Types Assigned https://security.netapp.com/advisory/ntap-20210226-0005/ Third Party Advisory Changed Reference Type https://www.debian.org/security/2021/dsa-4865 No Types Assigned https://www.debian.org/security/2021/dsa-4865 Third Party Advisory Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Added CPE Configuration OR *cpe:2.3:a:netapp:e-series_santricity_os_controller:*:*:*:*:*:*:*:* versions from (including) 11.0.0 up to (including) 11.60.3 -
CVE Modified by [email protected]
Feb. 28, 2021
Action Type Old Value New Value Added Reference https://www.debian.org/security/2021/dsa-4865 [No Types Assigned] -
CVE Modified by [email protected]
Feb. 26, 2021
Action Type Old Value New Value Added Reference https://security.netapp.com/advisory/ntap-20210226-0005/ [No Types Assigned] -
Initial Analysis by [email protected]
Feb. 10, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:A/AC:L/Au:S/C:N/I:P/A:N) Added CVSS V3.1 NIST AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N Changed Reference Type https://docs.docker.com/engine/release-notes/#20103 No Types Assigned https://docs.docker.com/engine/release-notes/#20103 Release Notes, Vendor Advisory Changed Reference Type https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c No Types Assigned https://github.com/moby/moby/commit/64bd4485b3a66a597c02c95f5776395e540b2c7c Patch, Third Party Advisory Changed Reference Type https://github.com/moby/moby/releases/tag/v19.03.15 No Types Assigned https://github.com/moby/moby/releases/tag/v19.03.15 Release Notes, Third Party Advisory Changed Reference Type https://github.com/moby/moby/releases/tag/v20.10.3 No Types Assigned https://github.com/moby/moby/releases/tag/v20.10.3 Release Notes, Third Party Advisory Changed Reference Type https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc No Types Assigned https://github.com/moby/moby/security/advisories/GHSA-7452-xqpj-6rpc Third Party Advisory Added CPE Configuration OR *cpe:2.3:a:docker:docker:*:*:*:*:*:*:*:* versions up to (excluding) 19.03.15 *cpe:2.3:a:docker:docker:*:*:*:*:*:*:*:* versions from (including) 20.0.0 up to (excluding) 20.10.3 -
CVE Modified by [email protected]
Feb. 02, 2021
Action Type Old Value New Value Changed 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. 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.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-21284 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-21284
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.05 }} 0.00%
score
0.14213
percentile