CyberSecBulletin
CVE-2022-0024NVD status: Modified

PAN-OS: Improper Neutralization of Special Elements

CVE-2022-0024 is a high-severity improper neutralization of special elements vulnerability in PAN-OS from Palo Alto Networks, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists versions 9.1.13, 10.1.5, 9.0.16 as the first without the flaw, so updating PAN-OS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.61% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update PAN-OS to 9.1.13 or 10.1.5 or 9.0.16 or 8.1.23, whichever matches your release line, or a later version.
  2. Read the advisory on security.paloaltonetworks.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Palo Alto NetworksPAN-OS9.1 up to, but not including, 9.1.13; 10.1 up to, but not including, 10.1.5; 9.0 up to, but not including, 9.0.16; 8.1 up to, but not including, 8.1.23; 10.0 up to, but not including, 10.0.109.1.13, 10.1.5, 9.0.16, 8.1.23, 10.0.10

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
HighAdministrator-level access is required first.
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:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighCNA (paloaltonetworks.com)
CVSS 3.17.2HighNVD
CVSS 2.09.0HighNVD

Official description

A vulnerability exists in Palo Alto Networks PAN-OS software that enables an authenticated network-based PAN-OS administrator to upload a specifically created configuration that disrupts system processes and potentially execute arbitrary code with root privileges when the configuration is committed on both hardware and virtual firewalls. This issue does not impact Panorama appliances or Prisma Access customers. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.23; PAN-OS 9.0 versions earlier than PAN-OS 9.0.16; PAN-OS 9.1 versions earlier than PAN-OS 9.1.13; PAN-OS 10.0 versions earlier than PAN-OS 10.0.10; PAN-OS 10.1 versions earlier than PAN-OS 10.1.5.

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

The underlying weakness: Improper Neutralization of Special Elements

The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as control elements or syntactic markers when they are sent to a downstream component.

How developers prevent this class of flaw

  • Developers should anticipate that special elements (e.g. delimiters, symbols) will be injected into input vectors of their product. One defense is to create an allowlist (e.g. a regular expression) that defines valid input according to the requirements specifications. Strictly filter any input that does not match against the allowlist. Properly encode your output, and quote any elements that have special meaning to the component with which you are communicating.
  • Use and specify an appropriate output encoding to ensure that the special elements are well-defined. A normal byte sequence in one encoding could be a special element in another.
  • Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.

More Improper Neutralization of Special Elements vulnerabilities (CWE-138)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in PAN-OS

All PAN-OS vulnerabilities

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