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CVE-2022-24299NVD status: Modified

Improper input validation vulnerability in pfSense CE and pfSense Plus (pfSense CE software…

CVE-2022-24299 is a high-severity improper input validation vulnerability in pfSense CE and pfSense Plus from pfSense, with a CVSS 3.1 base score of 8.8 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 1.93% chance of exploitation within 30 days, higher than 80% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Pfsense to 2.6.0 or a later version.
  2. Update Pfsense Plus to 22.01 or a later version.
  3. Read the advisory on docs.netgate.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
pfSensepfSense CE and pfSense PlusNot specified in the recordNot stated
NetgatePfsensebefore 2.6.02.6.0
NetgatePfsense Plusbefore 22.0122.01

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

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 2.06.5MediumNVD

Official description

Improper input validation vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions prior to 2.6.0 and pfSense Plus software versions prior to 22.01) allows a remote attacker with the privilege to change OpenVPN client or server settings to execute an arbitrary command.

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

The underlying weakness: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How developers prevent this class of flaw

  • Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build recognizers for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses.
  • Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
  • Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.

More Improper Input Validation vulnerabilities (CWE-20)

Timeline

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

References

Patches and release notes

Other vulnerabilities in pfSense CE and pfSense Plus

All pfSense CE and pfSense Plus vulnerabilities

Recent Improper Input Validation vulnerabilities

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