CVE-2026-72840

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29
https://www.vulncheck.com/advisories/openwrt-luci-luci-mod-system-mounts-acl-root-rce-via-crontab-write
https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 22:17

Updated : 2026-09-09 20:35

NVD link : CVE-2026-72840

Mitre link : CVE-2026-72840

CVE.ORG link : CVE-2026-72840

JSON object : View

Products Affected

No product.

CWE

CWE-266

Incorrect Privilege Assignment

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