7.1
HIGH CVSS 4.0
CVE-2026-85390
Checkmate through 3.11.0 Missing Authorization on Maintenance Window, Notification, and Check Deletion Routes
Description

Checkmate through 3.11.0 omits the isAllowed role guard middleware on maintenance-window, notification, and check-deletion routes, allowing read-only users to perform administrative actions. Attackers with user-role sessions can create arbitrary maintenance windows to silence alerts, modify notification channels, and delete monitor check history to erase incident evidence.

INFO

Published Date :

Sept. 3, 2026, 7:17 p.m.

Last Modified :

Sept. 3, 2026, 7:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-85390 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 HIGH [email protected]
CVSS 4.0 HIGH 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 HIGH [email protected]
Solution
Apply the vendor patch to restore access controls and prevent unauthorized administrative actions.
  • Update Checkmate to version 3.11.1 or later.
  • Verify access controls on maintenance, notification, and check-deletion routes.
  • Review audit logs for unauthorized administrative actions.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-85390 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-85390 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-85390 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-85390 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 03, 2026

    Action Type Old Value New Value
    Added Description Checkmate through 3.11.0 omits the isAllowed role guard middleware on maintenance-window, notification, and check-deletion routes, allowing read-only users to perform administrative actions. Attackers with user-role sessions can create arbitrary maintenance windows to silence alerts, modify notification channels, and delete monitor check history to erase incident evidence.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
    Added CWE CWE-862
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/85xxx/CVE-2026-85390.json">CVE-2026-85390</a>
    Added Reference https://github.com/bluewave-labs/Checkmate
    Added Reference https://github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/routes/checkRoutes.ts
    Added Reference https://github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/routes/maintenanceWindowRoutes.ts
    Added Reference https://github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/routes/notificationRoutes.ts
    Added Reference https://github.com/bluewave-labs/Checkmate/issues/3916
    Added Reference https://www.vulncheck.com/advisories/checkmate-through-3.11.0-missing-authorization-on-maintenance-window-notification-and-check-deletion-routes
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.