Which products and versions are affected by CVE-2021-40344?

Affected: Nagios Xi versions 5.8.5. The full list is in the CVE brief.

Is CVE-2021-40344 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2021-40344 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2021-40344?

No public exploit code is known.

Is there a fix for CVE-2021-40344?

No fixed version is listed yet; check the vendor advisory for mitigations.

How urgently should CVE-2021-40344 be patched?

Brandefense priority: patch immediately, because it is very likely to be exploited soon.

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Vulnerability Intelligence

CVE-2021-40344

High

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.

Published Oct 27, 2021 · Updated Aug 4, 2024

Key Facts

Patch immediately

CVE-2021-40344 is a high-severity vulnerability (CVSS 7.2 v3.1) affecting Nagios Xi.
It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
EPSS estimates a 65% probability of exploitation in the next 30 days.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

CVSS v3.1

7.2

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

EPSS (30-day exploit likelihood)

65%

Higher than 99.2% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

None known

Get the full CVE-2021-40344 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

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.

Affected Products

1 affected entries in total

Product	Affected versions	Fixed in
Nagios XiNagios	5.8.5	n/a

Timeline

Publicly disclosed
Oct 27, 2021
Last updated
Aug 4, 2024

Weakness Type

CWE-434 Unrestricted Upload of File with Dangerous Type

References

2 more references in the full CVE brief

FAQ

Common Questions.

An issue was discovered in Nagios XI 5.8.5.
Affected: Nagios Xi versions 5.8.5. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.

Is CVE-2021-40344 Running On Your Attack Surface?

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