CVE Vulnerabilities

CVE-2019-11328

Incorrect Permission Assignment for Critical Resource

Published: May 14, 2019 | Modified: Nov 07, 2023
CVSS 3.x
8.8
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
9 HIGH
AV:N/AC:L/Au:S/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

An issue was discovered in Singularity 3.1.0 to 3.2.0-rc2, a malicious user with local/network access to the host system (e.g. ssh) could exploit this vulnerability due to insecure permissions allowing a user to edit files within /run/singularity/instances/sing/<user>/<instance>. The manipulation of those files can change the behavior of the starter-suid program when instances are joined resulting in potential privilege escalation on the host.

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
Singularity Sylabs 3.1.0 *
Singularity Sylabs 3.2.0 3.2.0
Singularity Sylabs 3.2.0 3.2.0
Singularity Sylabs 3.2.0 3.2.0

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