CVE Vulnerabilities

CVE-2019-12777

Incorrect Permission Assignment for Critical Resource

Published: Jun 07, 2019 | Modified: Aug 24, 2020
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.2 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

An issue was discovered on the ENTTEC Datagate MK2, Storm 24, Pixelator, and E-Streamer MK2 with firmware 70044_update_05032019-482. They replace secure and protected directory permissions (set as default by the underlying operating system) with highly insecure read, write, and execute directory permissions for all users. By default, /usr/local and all of its subdirectories should have permissions set to only allow non-privileged users to read and execute from the tree structure, and to deny users from creating or editing files in this location. The ENTTEC firmware startup script permits all users to read, write, and execute (rwxrwxrwx) from the /usr, /usr/local, /usr/local/dmxis, and /usr/local/bin/ directories.

Weakness

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

Affected Software

Name Vendor Start Version End Version
Datagate_mk2_firmware Enttec 70044 70044

Potential Mitigations

  • Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
  • OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
  • This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
  • Be careful to avoid CWE-243 and other weaknesses related to jails.

References