cbcvebase.
CVE-2019-5021
published 2019-05-08

CVE-2019-5021: Versions of the Official Alpine Linux Docker images (since v3.3) contain a NULL password for the `root` user. This vulnerability appears to be the result of a…

PriorityP262critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
6.26%
92.7th percentile
Versions of the Official Alpine Linux Docker images (since v3.3) contain a NULL password for the `root` user. This vulnerability appears to be the result of a regression introduced in December of 2015. Due to the nature of this issue, systems deployed using affected versions of the Alpine Linux container which utilize Linux PAM, or some other mechanism which uses the system shadow file as an authentication database, may accept a NULL password for the `root` user.

Affected

5 ranges
VendorProductVersion rangeFixed in
f5big-ip_controller
gliderlabsdocker-alpine>= 3.3
opensuseleap
opensuseleap
paloaltocortex_xsoar

Detection & IOCsextracted from sources · hover to see the quote

  • Check /etc/shadow for a NULL (empty) password field for the root user — a line beginning with 'root::' indicates the vulnerable condition
  • Grep /etc/shadow for the pattern '^root::' to confirm the NULL root password is present in the container image
  • Scope detection to Official Alpine Linux Docker images version 3.3 through 3.9 (inclusive); images outside this range are not affected
  • Use the Tenable 'Unpassworded root Account' plugin (Default Unix Accounts family) to flag exploitable hosts with blank root passwords without requiring plugin updates
  • ·The vulnerability was introduced by a regression in December 2015 when a prior fix (patched in November 2015) was accidentally removed eight days later; affected images span Alpine Linux Docker versions 3.3 through 3.9
  • ·Cortex XSOAR (Demisto) conducted a scan of all Docker images in its Docker Hub repository and concluded none of its Alpine-based images are affected; the docker exec command is not exposed to external attackers in that product

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C
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