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CVE-2026-75025 (GCVE-0-2026-75025)

Vulnerability from cvelistv5 – Published: 2026-09-16 18:27 – Updated: 2026-09-16 18:27
VLAI
Title
Mattermost Desktop local network access from server-rendered content
Summary
Mattermost Desktop App versions <=6.2 6.2.2.0 Fixed an issue where Mattermost Desktop did not sufficiently restrict server-rendered content from accessing local or private network resources. Thanks to game0v3r for contributing to this improvement under the Mattermost responsible disclosure policy. Mattermost Advisory ID: MMSA-2026-00698
Severity
4.7 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
CWE
  • CWE-346 - Origin Validation Error
Assigner
References
URL Tags
https://mattermost.com/security-updates vendor-advisory
Impacted products
Vendor Product Version CPE status
Mattermost Mattermost Affected: 0 , ≤ 6.2.2 (semver)
Unaffected: 6.3.0
Unaffected: 6.2.3.0
guessed Create a notification for this product.
Credits
game0v3r
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "6.2.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "6.3.0"
            },
            {
              "status": "unaffected",
              "version": "6.2.3.0"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "game0v3r"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mattermost Desktop App versions \u003c=6.2 6.2.2.0 Fixed an issue where Mattermost Desktop did not sufficiently restrict server-rendered content from accessing local or private network resources. Thanks to game0v3r for contributing to this improvement under the Mattermost responsible disclosure policy. Mattermost Advisory ID: MMSA-2026-00698"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-346",
              "description": "CWE-346: Origin Validation Error",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-16T18:27:02.819Z",
        "orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
        "shortName": "Mattermost"
      },
      "references": [
        {
          "name": "MMSA-2026-00698",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost Desktop App to versions 6.3.0, 6.2.3.0 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2026-00698",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-69239"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Mattermost Desktop local network access from server-rendered content",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
    "cveId": "CVE-2026-75025",
    "datePublished": "2026-09-16T18:27:02.819Z",
    "dateReserved": "2026-08-17T14:33:41.253Z",
    "dateUpdated": "2026-09-16T18:27:02.819Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-75025",
      "date": "2026-09-17",
      "epss": "0.00146",
      "percentile": "0.04262"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-75025\",\"sourceIdentifier\":\"responsibledisclosure@mattermost.com\",\"published\":\"2026-09-16T19:17:33.430\",\"lastModified\":\"2026-09-16T19:30:49.967\",\"vulnStatus\":\"Awaiting Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Mattermost Desktop App versions \u003c=6.2 6.2.2.0 Fixed an issue where Mattermost Desktop did not sufficiently restrict server-rendered content from accessing local or private network resources. Thanks to game0v3r for contributing to this improvement under the Mattermost responsible disclosure policy. Mattermost Advisory ID: MMSA-2026-00698\"}],\"affected\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"affectedData\":[{\"vendor\":\"Mattermost\",\"product\":\"Mattermost\",\"defaultStatus\":\"unaffected\",\"versions\":[{\"version\":\"0\",\"lessThanOrEqual\":\"6.2.2\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.3.0\",\"status\":\"unaffected\"},{\"version\":\"6.2.3.0\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N\",\"baseScore\":4.7,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"REQUIRED\",\"scope\":\"CHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":2.8,\"impactScore\":1.4}]},\"weaknesses\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-346\"}]}],\"references\":[{\"url\":\"https://mattermost.com/security-updates\",\"source\":\"responsibledisclosure@mattermost.com\"}]}}"
  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


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