Vulnerability-Lookup

GHSA-6645-RFG8-RHRM

Vulnerability from github – Published: 2026-09-16 00:31 – Updated: 2026-09-16 00:31

Details

Netcore NR268 firmware version 1.7.121109 has an improper integrity verification flaw in mtd_write allowing forged firmware authenticity checks. Attackers can exploit put_file.cgi and check_image_uuid.c to bypass firmware signature validation and load unauthorized firmware images.

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-2026-76852"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-354"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-15T22:16:58Z",
    "severity": "HIGH"
  },
  "details": "Netcore NR268 firmware version 1.7.121109 has an improper integrity verification flaw in mtd_write allowing forged firmware authenticity checks. Attackers can exploit put_file.cgi and check_image_uuid.c to bypass firmware signature validation and load unauthorized firmware images.",
  "id": "GHSA-6645-rfg8-rhrm",
  "modified": "2026-09-16T00:31:29Z",
  "published": "2026-09-16T00:31:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-76852"
    },
    {
      "type": "WEB",
      "url": "https://github.com/draw-ctf/netcore-router-public-refs/blob/main/2026.08.19-netcore-nr268-firmware-forgery.md"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/netcore-nr268-1.7.121109-forgeable-firmware-authenticity-check-in-mtd-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-2026-76852 (GCVE-0-2026-76852)

Vulnerability from cvelistv5 – Published: 2026-09-15 21:57 – Updated: 2026-09-15 21:57

Title

Netcore NR268 1.7.121109 Forgeable Firmware Authenticity Check in mtd_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

CWE

CWE-354 - Improper Validation of Integrity Check Value

Assigner

VulnCheck mitre root

References

2 references

URL	Tags
https://github.com/draw-ctf/netcore-router-public…	third-party-advisory
https://www.vulncheck.com/advisories/netcore-nr26…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
Netcore	NR268	Affected: 1.7.121109 (custom)

Date Public

2026-09-04 00:00

Credits

Zhou Ao Yin Luxing Jiang Yuxuan Liu Xin @Nebusec

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "NR268",
          "vendor": "Netcore",
          "versions": [
            {
              "status": "affected",
              "version": "1.7.121109",
              "versionType": "custom"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Zhou Ao"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Yin Luxing"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Jiang Yuxuan"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "Liu Xin"
        },
        {
          "lang": "en",
          "type": "finder",
          "value": "@Nebusec"
        }
      ],
      "datePublic": "2026-09-04T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "Netcore NR268 firmware version 1.7.121109 has an improper integrity verification flaw in mtd_write allowing forged firmware authenticity checks. Attackers can exploit put_file.cgi and check_image_uuid.c to bypass firmware signature validation and load unauthorized firmware images."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          },
          "format": "CVSS"
        },
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "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",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-354",
              "description": "Improper Validation of Integrity Check Value",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-15T21:57:48.762Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
      },
      "references": [
        {
          "name": "Netcore router public references: Forgeable Firmware Authenticity Check in mtd_write",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://github.com/draw-ctf/netcore-router-public-refs/blob/main/2026.08.19-netcore-nr268-firmware-forgery.md"
        },
        {
          "name": "VulnCheck Advisory: Netcore NR268 1.7.121109 Forgeable Firmware Authenticity Check in mtd_write",
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/netcore-nr268-1.7.121109-forgeable-firmware-authenticity-check-in-mtd-write"
        }
      ],
      "title": "Netcore NR268 1.7.121109 Forgeable Firmware Authenticity Check in mtd_write",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-76852",
    "datePublished": "2026-09-15T21:57:48.762Z",
    "dateReserved": "2026-08-19T21:47:08.935Z",
    "dateUpdated": "2026-09-15T21:57:48.762Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.