CyberSecBulletin
CVE-2022-20732NVD status: Modified

Cisco Virtualized Infrastructure Manager: Incorrect Default Permissions

CVE-2022-20732 is a high-severity incorrect default permissions vulnerability in Cisco Virtualized Infrastructure Manager from Cisco, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Virtualized Infrastructure Manager to 4.2.2 or a later version.
  2. Read the advisory on tools.cisco.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco Virtualized Infrastructure ManagerNot specified in the recordNot stated
CiscoVirtualized Infrastructure Managerbefore 4.2.24.2.2

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA (cisco.com)
CVSS 3.17.8HighNVD
CVSS 2.04.6MediumNVD

Official description

A vulnerability in the configuration file protections of Cisco Virtualized Infrastructure Manager (VIM) could allow an authenticated, local attacker to access confidential information and elevate privileges on an affected device. This vulnerability is due to improper access permissions for certain configuration files. An attacker with low-privileged credentials could exploit this vulnerability by accessing an affected device and reading the affected configuration files. A successful exploit could allow the attacker to obtain internal database credentials, which the attacker could use to view and modify the contents of the database. The attacker could use this access to the database to elevate privileges on the affected device.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Default Permissions

During installation, installed file permissions are set to allow anyone to modify those files.

How developers prevent this class of flaw

  • The architecture needs to access and modification attributes for files to only those users who actually require those actions.
  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Incorrect Default Permissions vulnerabilities (CWE-276)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Incorrect Default Permissions vulnerabilities

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