CVE-2025-9076 (GCVE-0-2025-9076)
Vulnerability from cvelistv5
Published
2025-09-15 10:06
Modified
2025-09-15 14:05
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
CWE
Summary
Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.
References
responsibledisclosure@mattermost.comhttps://mattermost.com/security-updates
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 10.10.0   ≤ 10.10.1
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-9076",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-09-15T14:05:07.348669Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-09-15T14:05:16.235Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "10.10.1",
              "status": "affected",
              "version": "10.10.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "10.11.0"
            },
            {
              "status": "unaffected",
              "version": "10.10.2"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "daw10"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mattermost versions 10.10.x \u003c= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-15T10:06:15.094Z",
        "orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
        "shortName": "Mattermost"
      },
      "references": [
        {
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 10.11.0, 10.10.2 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2025-00513",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-64926"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Mattermost Server exposes sensitive user credentials during shared channel membership synchronization"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
    "cveId": "CVE-2025-9076",
    "datePublished": "2025-09-15T10:06:15.094Z",
    "dateReserved": "2025-08-15T15:26:17.148Z",
    "dateUpdated": "2025-09-15T14:05:16.235Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-9076\",\"sourceIdentifier\":\"responsibledisclosure@mattermost.com\",\"published\":\"2025-09-15T10:15:32.450\",\"lastModified\":\"2025-09-15T15:21:42.937\",\"vulnStatus\":\"Undergoing Analysis\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Mattermost versions 10.10.x \u003c= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N\",\"baseScore\":6.5,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"HIGH\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":1.2,\"impactScore\":5.2}]},\"weaknesses\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-862\"}]}],\"references\":[{\"url\":\"https://mattermost.com/security-updates\",\"source\":\"responsibledisclosure@mattermost.com\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2025-9076\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2025-09-15T14:05:07.348669Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2025-09-15T14:05:11.941Z\"}}], \"cna\": {\"title\": \"Mattermost Server exposes sensitive user credentials during shared channel membership synchronization\", \"source\": {\"defect\": [\"https://mattermost.atlassian.net/browse/MM-64926\"], \"advisory\": \"MMSA-2025-00513\", \"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"daw10\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 6.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"HIGH\", \"confidentialityImpact\": \"HIGH\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"Mattermost\", \"product\": \"Mattermost\", \"versions\": [{\"status\": \"affected\", \"version\": \"10.10.0\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"10.10.1\"}, {\"status\": \"unaffected\", \"version\": \"10.11.0\"}, {\"status\": \"unaffected\", \"version\": \"10.10.2\"}], \"defaultStatus\": \"unaffected\"}], \"solutions\": [{\"lang\": \"en\", \"value\": \"Update Mattermost to versions 10.11.0, 10.10.2 or higher.\"}], \"references\": [{\"url\": \"https://mattermost.com/security-updates\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Mattermost versions 10.10.x \u003c= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user objects. This vulnerability affects Mattermost Server instances with shared channels enabled.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-862\", \"description\": \"CWE-862: Missing Authorization\"}]}], \"providerMetadata\": {\"orgId\": \"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee\", \"shortName\": \"Mattermost\", \"dateUpdated\": \"2025-09-15T10:06:15.094Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2025-9076\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2025-09-15T14:05:16.235Z\", \"dateReserved\": \"2025-08-15T15:26:17.148Z\", \"assignerOrgId\": \"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee\", \"datePublished\": \"2025-09-15T10:06:15.094Z\", \"assignerShortName\": \"Mattermost\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.