CVE-2021-33179

mediumpriority · track · 28EPSS 0.117 · 96 %ileDEEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

11.7% (96th) EPSS

CVSS 4.3 · medium

Is it mine?

12 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

The general user interface in Nagios XI versions prior to 5.8.4 is vulnerable to authenticated reflected cross-site scripting. An authenticated victim, who accesses a specially crafted malicious URL, would unknowingly execute the attached payload.

cvss

Technical severity, 0–10. One row per scoring source.

6.1

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.1mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 2.7

v3.15.6mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

affected products (12)

Products and version ranges known to be affected.

Checkmk Checkmkall versionscert_bundDEcpe:/a:tribe29:checkmk:-
Checkmk Checkmk <2.0.0p18all versionscert_bundDE
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Nagios Enterprises Nagios XI <5.8.4all versionscert_bundDE
Nagios Enterprises Nagios XI <5.8.5all versionscert_bundDE
Nagios Enterprises Nagios XI <5.8.6all versionscert_bundDE
Nagios Enterprises Nagios XI< 5.8.4cert_bundDE
Nagios Enterprises Nagios XI< 5.8.5cert_bundDE
Nagios Enterprises Nagios XI< 5.8.6cert_bundDE
Tribe29 Checkmk< 2.0.0p18cert_bundDE
Nagios Nagios XI≤ <5.8.4enisa_euvdEU
nagios nagios xi< 5.8.4nvdUScpe:2.3:a:nagios:nagios_xi:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2025-0911Nagios Enterprises Nagios XI: Mehrere SchwachstellenDeutsch2021-10-14csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Nagios Enterprises Nagios XI ausnutzen, um Dateien zu manipulieren oder einen Cross-Site-Scripting-Angriff durchzuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2021-10-14modified 2026-06-17

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Related entries.

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+53008 more

references (4)

External citations — patches, advisories, analysis.

scry

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