CyberSecBulletin
CVE-2022-20777NVD status: Modified

Cisco Enterprise NFV Infrastructure Software: Improper Access Control

CVE-2022-20777 is a critical-severity improper access control vulnerability in Cisco Enterprise NFV Infrastructure Software from Cisco, with a CVSS 3.1 base score of 9.9 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 11.1% chance of exploitation within 30 days, which is in the top 4.01% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Enterprise Nfv Infrastructure Software to 4.7.1 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco Enterprise NFV Infrastructure SoftwareNot specified in the recordNot stated
CiscoEnterprise Nfv Infrastructure Softwarebefore 4.7.14.7.1

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
NetworkCan be exploited remotely over a network, including the internet.
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
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.9CriticalCNA (cisco.com)
CVSS 3.19.9CriticalNVD
CVSS 2.09.0HighNVD

Official description

Multiple vulnerabilities in Cisco Enterprise NFV Infrastructure Software (NFVIS) could allow an attacker to escape from the guest virtual machine (VM) to the host machine, inject commands that execute at the root level, or leak system data from the host to the VM. For more information about these vulnerabilities, see the Details section of this advisory.

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

The underlying weakness: Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • 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 Improper Access Control vulnerabilities (CWE-284)

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

Other vulnerabilities in Cisco Enterprise NFV Infrastructure Software

All Cisco Enterprise NFV Infrastructure Software vulnerabilities

Recent Improper Access Control vulnerabilities

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