CVE-2021-40344

mediumpriority · attend · 52EPSS 0.648 · 99 %ileEUUS

grimoire priorityP1 · Urgent

Exploitable?

—

no known exploitation

Likely / severe?

64.8% (99th) EPSS

CVSS 6.5 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

An issue was discovered in Nagios XI 5.8.5. In the Custom Includes section of the Admin panel, an administrator can upload files with arbitrary extensions as long as the MIME type corresponds to an image. Therefore it is possible to upload a crafted PHP script to achieve remote command execution.

cvss

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

7.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–7.2

v2.06.5mediumAV:N/AC:L/Au:S/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8 · impact 6.4

v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.2 · impact 5.9

v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USprimary

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
nagios nagios xi= 5.8.5nvdUScpe:2.3:a:nagios:nagios_xi:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-10-26modified 2026-06-17

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+5032 more

references (11)

External citations — patches, advisories, analysis.

scry

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