CyberSecBulletin
CVE-2024-20286NVD status: Analyzed

Cisco NX-OS Software: Protection Mechanism Failure

CVE-2024-20286 is a high-severity protection mechanism failure vulnerability in Cisco NX-OS Software from Cisco, with a CVSS 3.1 base score of 8.8 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. Affected Cisco NX-OS Software versions: 8.2(5); 7.3(5)D1(1); 8.4(2), and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.19% 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. Check which version of Cisco NX-OS Software you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco NX-OS Software8.2(5); 7.3(5)D1(1); 8.4(2); 6.2(2); 8.4(3); 9.2(3); 7.0(3)I5(2); 8.2(1); and 32 more rangesNot stated
CiscoNx-os9.3\(13\)Not stated

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
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:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.15.3MediumCNA (cisco.com)
CVSS 3.18.8HighNVD

Official description

A vulnerability in the Python interpreter of Cisco NX-OS Software could allow an authenticated, low-privileged, local attacker to escape the Python sandbox and gain unauthorized access to the underlying operating system of the device. The vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by manipulating specific functions within the Python interpreter. A successful exploit could allow an attacker to escape the Python sandbox and execute arbitrary commands on the underlying operating system with the privileges of the authenticated user.  Note: An attacker must be authenticated with Python execution privileges to exploit these vulnerabilities. For more information regarding Python execution privileges, see product-specific documentation, such as the section of the Cisco Nexus 9000 Series NX-OS Programmability Guide.

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

The underlying weakness: Protection Mechanism Failure

The product does not use or incorrectly uses a protection mechanism that provides sufficient defense against directed attacks against the product.

More Protection Mechanism Failure vulnerabilities (CWE-693)

Timeline

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

References

Other vulnerabilities in Cisco NX-OS Software

All Cisco NX-OS Software vulnerabilities

Recent Protection Mechanism Failure vulnerabilities

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