5.2
MEDIUM CVSS 3.1
CVE-2026-33921
Npcap driver installed without administrator-only access restriction on Windows in Arc before v2.7.0
Description

The Windows installer deployed Npcap leaving its access restriction option at the insecure default value, so the driver was accessible to every local user of the host instead of being restricted to administrators only. A local user without administrative privileges could use the Npcap driver to capture the traffic reaching the host, which discloses information belonging both to the host and to other systems on the same network segment, and to send arbitrary raw packets on that segment.

INFO

Published Date :

Aug. 11, 2026, 10:17 a.m.

Last Modified :

Aug. 11, 2026, 10:17 a.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-33921 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Nozomi_networks arc
1 Nozominetworks arc
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM bec8025f-a851-46e5-b3a3-058e6b0aa23c
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM bec8025f-a851-46e5-b3a3-058e6b0aa23c
CVSS 4.0 MEDIUM [email protected]
Solution
Configure Npcap access restrictions to prevent unauthorized local user access.
  • Update Npcap to a version with secure defaults.
  • Configure Npcap to restrict driver access to administrators.
  • Review Npcap installation and configuration settings.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-33921.

URL Resource
https://security.nozominetworks.com/NN-2026:14-01
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-33921 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-33921 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-33921 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-33921 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 11, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Nozomi Networks', 'product': 'Arc', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '2.7.0', 'versionType': 'semver'}], 'platforms': ['Windows'], 'defaultStatus': 'unaffected'}]
    Added Description The Windows installer deployed Npcap leaving its access restriction option at the insecure default value, so the driver was accessible to every local user of the host instead of being restricted to administrators only. A local user without administrative privileges could use the Npcap driver to capture the traffic reaching the host, which discloses information belonging both to the host and to other systems on the same network segment, and to send arbitrary raw packets on that segment.
    Added CVSS V4.0 AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
    Added CWE CWE-1188
    Added Reference https://security.nozominetworks.com/NN-2026:14-01
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.