RCE in Nozomi Networks Arc

CVE-2026-33921

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.001 (2.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33921: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33921?
CVE-2026-33921 is a medium-severity vulnerability in Nozomi Networks Arc, classified under Initialization of a Resource with an Insecure Default. CVSS score: 5.2/10. Published 2026-08-11.
How severe is CVE-2026-33921?
Medium severity. CVSS v3 base score is 5.2 out of 10.