Vulnerability-Lookup

GHSA-6VFC-74MF-QRMJ

Vulnerability from github – Published: 2026-08-14 00:32 – Updated: 2026-08-14 00:32

Details

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.

Severity

8.8 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

8.7 (High)


                  
                    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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-72840"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-266"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-13T22:17:23Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-6vfc-74mf-qrmj",
  "modified": "2026-08-14T00:32:01Z",
  "published": "2026-08-14T00:32:01Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72840"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/openwrt-luci-luci-mod-system-mounts-acl-root-rce-via-crontab-write"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-72840 (GCVE-0-2026-72840)

Vulnerability from cvelistv5 – Published: 2026-08-13 21:54 – Updated: 2026-08-14 19:03

Title

OpenWrt LuCI luci-mod-system-mounts ACL Root RCE via Crontab Write

Summary

Severity

8.7 (High)


                        
                          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

8.8 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-14 19:03 UTC

CWE

CWE-266 - Incorrect Privilege Assignment

Assigner

VulnCheck

References

2 references

URL	Tags
https://github.com/openwrt/luci/security/advisori…	vendor-advisory
https://www.vulncheck.com/advisories/openwrt-luci…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
openwrt	luci

Date Public

2026-07-21 00:00

Credits

lujiefsi

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-72840",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-14T19:03:28.552422Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-08-14T19:03:37.329Z",
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        },
        "references": [
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            "tags": [
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            "url": "https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "product": "luci",
          "vendor": "openwrt"
        }
      ],
      "cpeApplicability": [
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              "operator": "OR"
            }
          ]
        }
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      "credits": [
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          "lang": "en",
          "type": "reporter",
          "value": "lujiefsi"
        }
      ],
      "datePublic": "2026-07-21T00:00:00.000Z",
      "descriptions": [
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          "lang": "en",
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        }
      ],
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            "subConfidentialityImpact": "NONE",
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            "vectorString": "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",
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            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
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          "descriptions": [
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      },
      "references": [
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          ],
          "url": "https://github.com/openwrt/luci/security/advisories/GHSA-v5f9-62c7-cw29"
        },
        {
          "name": "VulnCheck Advisory: OpenWrt LuCI luci-mod-system-mounts ACL Root RCE via Crontab Write",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/openwrt-luci-luci-mod-system-mounts-acl-root-rce-via-crontab-write"
        }
      ],
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      "x_generator": {
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  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
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    "datePublished": "2026-08-13T21:54:39.948Z",
    "dateReserved": "2026-08-10T15:13:41.486Z",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-6VFC-74MF-QRMJ

CVE-2026-72840 (GCVE-0-2026-72840)

Tags

Sightings

Nomenclature