CVE-2025-12421 (GCVE-0-2025-12421)
Vulnerability from cvelistv5
Published
2025-11-27 17:47
Modified
2025-11-27 17:47
Severity ?
9.9 (Critical) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-303 - Incorrect Implementation of Authentication Algorithm
Summary
Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled (default: enabled) and RequireEmailVerification to be disabled (default: disabled).
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.0.0   ≤ 11.0.2
Version: 10.12.0   ≤ 10.12.1
Version: 10.11.0   ≤ 10.11.4
Version: 10.5.0   ≤ 10.5.12
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "11.0.2",
              "status": "affected",
              "version": "11.0.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.12.1",
              "status": "affected",
              "version": "10.12.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.11.4",
              "status": "affected",
              "version": "10.11.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.5.12",
              "status": "affected",
              "version": "10.5.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "11.1.0"
            },
            {
              "status": "unaffected",
              "version": "11.0.3"
            },
            {
              "status": "unaffected",
              "version": "10.12.2"
            },
            {
              "status": "unaffected",
              "version": "10.11.5"
            },
            {
              "status": "unaffected",
              "version": "10.5.13"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "daw10"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mattermost versions 11.0.x \u003c= 11.0.2, 10.12.x \u003c= 10.12.1, 10.11.x \u003c= 10.11.4, 10.5.x \u003c= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled (default: enabled) and RequireEmailVerification to be disabled (default: disabled)."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.9,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-303",
              "description": "CWE-303: Incorrect Implementation of Authentication Algorithm",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-11-27T17:47:04.944Z",
        "orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
        "shortName": "Mattermost"
      },
      "references": [
        {
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.1.0, 11.0.3, 10.12.2, 10.11.5, 10.5.13 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2025-00544",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-66299"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Account Takeover via Code Exchange Endpoint"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
    "cveId": "CVE-2025-12421",
    "datePublished": "2025-11-27T17:47:04.944Z",
    "dateReserved": "2025-10-28T16:54:12.491Z",
    "dateUpdated": "2025-11-27T17:47:04.944Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-12421\",\"sourceIdentifier\":\"responsibledisclosure@mattermost.com\",\"published\":\"2025-11-27T18:15:46.223\",\"lastModified\":\"2025-11-27T18:15:46.223\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Mattermost versions 11.0.x \u003c= 11.0.2, 10.12.x \u003c= 10.12.1, 10.11.x \u003c= 10.11.4, 10.5.x \u003c= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled (default: enabled) and RequireEmailVerification to be disabled (default: disabled).\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H\",\"baseScore\":9.9,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"CHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.1,\"impactScore\":6.0}]},\"weaknesses\":[{\"source\":\"responsibledisclosure@mattermost.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-303\"}]}],\"references\":[{\"url\":\"https://mattermost.com/security-updates\",\"source\":\"responsibledisclosure@mattermost.com\"}]}}"
  }
}


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.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • 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.