Vulnerability · Published Aug 13, 2026 · Assigned by VulnCheck
CVE-2026-72840OpenWrt LuCI luci-mod-system-mounts ACL Root RCE via Crontab Write
High 8.8
In plain English
A high-severity security flaw in luci from openwrt. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 39% of all known vulnerabilities).
Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.4%top 61.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
Weakness: CWE-266 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- GitHub Security Advisory (GHSA-v5f9-62c7-cw29) vendor-advisory
- VulnCheck Advisory: OpenWrt LuCI luci-mod-system-mounts ACL Root RCE via Crontab Write third-party-advisory