What is CVE-2023-26999?

CVE-2023-26999 is a critical-severity vulnerability in Netscout Ngeniusone, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2024-01-09.

How severe is CVE-2023-26999?

Critical severity. CVSS v3 base score is 9.8 out of 10.

XXE in Netscout Ngeniusone

CVE-2023-26999

An issue found in NetScout nGeniusOne v.6.3.4 allows a remote attacker to execute arbitrary code and cause a denial of service via a crafted file.

Vulnerability class: XXE (XML External Entity)

Published 2024-01-09 · last modified 2026-07-09.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (63.2th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 63.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: +0.000

Affected products

Netscout Ngeniusone — versions 6.3.4

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

References

af854a3a-2127-422b-91ae-364da2661108 (Product)
af854a3a-2127-422b-91ae-364da2661108 (Broken Link)
piotrryciak.com/posts/netscout-multiple-vulnerabilities/ (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2023-26999?: CVE-2023-26999 is a critical-severity vulnerability in Netscout Ngeniusone, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 9.8/10. Published 2024-01-09.
How severe is CVE-2023-26999?: Critical severity. CVSS v3 base score is 9.8 out of 10.