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.
References7
- github.com/bluewave-labs/Checkmate
- github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/…
- github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/…
- github.com/bluewave-labs/Checkmate/blob/v3.11.0/server/src/api/…
- github.com/bluewave-labs/Checkmate/issues/3916
- www.vulncheck.com/advisories/checkmate-through-3.11.0-missing-a…
- github.com/bluewave-labs/Checkmate/issues/3916
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/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 - EPSS — exploit probability
- 0% percentile: 42 · as of 3 November 2026
- CWE
- CWE-862
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.