Checkmk: Improper Handling of Insufficient Permissions or Privileges
CVE-2026-24096 is a high-severity improper handling of insufficient permissions or privileges vulnerability in Checkmk, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 2.5.0b2, 2.4.0p25 as the first without the flaw, so updating Checkmk to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.24% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Checkmk to 2.5.0b2 or 2.4.0p25, whichever matches your release line, or a later version.
- Read the advisory on checkmk.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Checkmk | Checkmk | 2.5.0b1 up to, but not including, 2.5.0b2; 2.4.0 up to, but not including, 2.4.0p25 | 2.5.0b2, 2.4.0p25 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 5.3 | Medium | CNA (checkmk.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
Insufficient permission validation on multiple REST API Quick Setup endpoints in Checkmk 2.5.0 (beta) before version 2.5.0b2 and 2.4.0 before version 2.4.0p25 allows low-privileged users to perform unauthorized actions or obtain sensitive information
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Handling of Insufficient Permissions or Privileges
The product does not handle or incorrectly handles when it has insufficient privileges to access resources or functionality as specified by their permissions. This may cause it to follow unexpected code paths that may leave the product in an invalid state.
How developers prevent this class of flaw
- Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
- Always check to see if you have successfully accessed a resource or system functionality, and use proper error handling if it is unsuccessful. Do this even when you are operating in a highly privileged mode, because errors or environmental conditions might still cause a failure. For example, environments with highly granular permissions/privilege models, such as Windows or Linux capabilities, can cause unexpected failures.
More Improper Handling of Insufficient Permissions or Privileges vulnerabilities (CWE-280)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in Checkmk
- 9.4 Critical severity
- 9.4 Critical severity
- 9.4 Critical severity
- 7.1 High severity
- 8.6 High severity
- 7.8 High severity
Recent Improper Handling of Insufficient Permissions or Privileges vulnerabilities
- 7.8 High severity
- 8.4 High severity
- 8.2 High severity
- 8.1 High severity
- 7.8 High severity
- 8.8 High severity
Spotted an error? Tell us.