CVE-2026-117611

High

Description

Improper certificate validation in Checkmk <2.5.0p18, <2.4.0p39, <2.3.0p52 and 2.2.0 (EOL): the Certificate Authority stores bundled with "certifi" and "webpki-roots" include a root CA that trusts eMudhra (emSign) intermediate certificates whose private keys are public.

SeverityHigh

CVSS7.1

Exploit probability—

ProductCheckmk

PublishedOct 29, 2026

First seenNov 4, 2026

Weakness typeCWE-295CWE-295 CWE-1395CWE-1395

How to fix

Update

Checkmk GmbH Checkmk2.5.0p18, 2.4.0p39, 2.3.0p52 or later

Vendor advisories

checkmk.com/werk/22623
checkmk.com/werk/22169

Affected products

Product	Affected versions	Fixed in
Checkmk GmbH Checkmk	2.5.0 ≤ v < 2.5.0p18, 2.4.0 ≤ v < 2.4.0p39, 2.3.0 ≤ v < 2.3.0p52, 2.2.0	2.5.0p18, 2.4.0p39, 2.3.0p52

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