docker docker CVE-2021-21284 vulnerability in Docker and Other Products
Published on February 2, 2021

privilege escalation in Moby

product logo product logo product logo
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.

Github Repository Vendor Advisory Vendor Advisory NVD

Vulnerability Analysis

Attack Vector:
ADJACENT_NETWORK
Attack Complexity:
LOW
Privileges Required:
LOW
User Interaction:
NONE
Scope:
CHANGED
Confidentiality Impact:
NONE
Integrity Impact:
HIGH
Availability Impact:
NONE

Weakness Type

What is a Directory traversal Vulnerability?

The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

CVE-2021-21284 has been classified to as a Directory traversal vulnerability or weakness.


Products Associated with CVE-2021-21284

You can be notified by email with stack.watch whenever vulnerabilities like CVE-2021-21284 are published in these products:

Docker
 
NetApp E Series Santricity Os Controller
 
Debian Linux
 

Affected Versions

moby:

Exploit Probability

EPSS
0.02%
Percentile
5.03%

EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.