CVE-2026-72840

HIGH CVSS 4.0: 8.7 EPSS 0.30%
Updated Aug 14, 2026
OpenWrt
Parameter Value
CVSS 8.7 (HIGH)
Type CWE-266 (Incorrect Privilege Assignment)
Vendor OpenWrt
Public PoC No

OpenWrt LuCI contains an overly permissive ACL definition in luci-mod-system-mounts that grants write access to /etc/crontabs/root to users intended only for mount configuration. Authenticated users with only the mount-configuration ACL group can append arbitrary cron entries via ubus file.write, which the default busybox crond daemon executes as root within one minute.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0