CVE-2025-65000: Checkmk · Improper Removal of Sensitive Information Before Storage or Transfer
Affects CheckmkSource CVE Database V5
Not known to be exploited · CVSS 2.3 Low.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:L/SA:LExploitation evidence
Disclosed: evidence found.
CVE published 18 Dec 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Checkmk GmbH Checkmk | Affected
| Fixed in– |
AI-suggested
Until an official patch is released, European organizations should take the following specific steps: 1) Restrict access to the Checkmk web interface and specifically to the rule configuration pages to trusted administrators only, using strong authentication and network segmentation. 2) Audit current deployments to identify if vulnerable versions (2.3.0 and 2.4.0p18 or earlier) are in use and plan immediate upgrades once patches are available. 3) Rotate SSH keys associated with the 'Remote alert handlers (Linux)' rule to invalidate any potentially exposed keys. 4) Monitor logs for unusual alert handler activity or unauthorized access attempts. 5) Implement strict role-based access controls (RBAC) within Checkmk to minimize privilege exposure. 6) Consider disabling or limiting the use of remote alert handlers if not essential. 7) Educate administrators about the risks of exposing sensitive data in web interfaces and enforce secure development and deployment practices. These targeted measures go beyond generic advice by focusing on the specific vectors and components involved in this vulnerability.
Description
CVE-2025-65000 is a low-severity vulnerability in Checkmk versions 2.3.0 and 2.4.0p18 and earlier, where SSH private keys for the 'Remote alert handlers (Linux)' rule were exposed in the HTML source of the rule page. This exposure could allow unauthorized users with some level of access to trigger predefined alert handlers on affected hosts. The vulnerability arises from improper removal of sensitive information before storage or transfer (CWE-212). Although the CVSS score is low (2.3), the exposure of private keys poses a confidentiality risk. No known exploits are currently reported in the wild.