OpenWrt luci-mod-system-mounts /etc/crontabs/root file.write privileges management

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.50

Summaryinfo

A vulnerability was found in OpenWrt. It has been declared as problematic. This vulnerability affects the function file.write of the file /etc/crontabs/root of the component luci-mod-system-mounts. Executing a manipulation can lead to privileges management. This vulnerability is registered as CVE-2026-72840. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability has been found in OpenWrt (version now known) and classified as problematic. This vulnerability affects the function file.write of the file /etc/crontabs/root of the component luci-mod-system-mounts. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect integrity, and availability. CVE summarizes:

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 advisory is shared for download at github.com. This vulnerability was named CVE-2026-72840 since 08/10/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/14/2026). The MITRE ATT&CK project declares the attack technique as T1068.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/10/2026 CVE reserved
08/13/2026 +3 days VulDB entry created
08/14/2026 +0 days Advisory disclosed
08/14/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-72840 (🔒)
GCVE (CVE): GCVE-0-2026-72840
GCVE (VulDB): GCVE-100-389920

Entryinfo

Created: 08/14/2026 00:26
Changes: 08/14/2026 00:26 (53)
Complete: 🔍
Cache ID: 216::103

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