CVE-2026-72840CWE-266

CVE-2026-72840

High · published August 14, 2026

CVSS v3.1

8.8

EPSS

Percentile

37.4

In the wild

Unconfirmed

What it is

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.

The record

Technical detail

CVSS v3.1: 8.8 · HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0: 8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS: 0.00442 · 37.4th percentile
Weakness: CWE-266 · Incorrect Privilege Assignment
Published: 2026-08-14T02:17Z

References (3)

https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29 · [email protected]https://www.vulncheck.com/advisories/openwrt-luci-luci-mod-system-mounts-acl-root-rce-via-crontab-write · [email protected]https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29 · 134c704f-9b21-4f2e-91b3-4a467353bcc0

EPSS history

Timeline

13 AUG 21:54Z
OpenWrt LuCI luci-mod-system-mounts ACL Root RCE via Crontab Write
cvelistv5