FKIE_CVE-2026-2455

Vulnerability from fkie_nvd - Published: 2026-03-16 15:16 - Updated: 2026-06-17 10:30
Severity
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Summary
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to canonicalize IPv4-mapped IPv6 addresses before reserved IP validation which allows an attacker to perform SSRF attacks against internal services via IPv4-mapped IPv6 literals (e.g., [::ffff:127.0.0.1]).. Mattermost Advisory ID: MMSA-2026-00585
References
responsibledisclosure@mattermost.comhttps://mattermost.com/security-updatesVendor Advisory
Impacted products
Vendor Product Version
mattermost mattermost_server *
mattermost mattermost_server *
mattermost mattermost_server *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "11.3.0",
              "status": "affected",
              "version": "11.3.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "11.2.2",
              "status": "affected",
              "version": "11.2.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.11.10",
              "status": "affected",
              "version": "10.11.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "11.4.0"
            },
            {
              "status": "unaffected",
              "version": "11.3.1"
            },
            {
              "status": "unaffected",
              "version": "11.2.3"
            },
            {
              "status": "unaffected",
              "version": "10.11.11"
            }
          ]
        }
      ],
      "source": "responsibledisclosure@mattermost.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B6E5F368-358C-429B-8F04-3C8DF4A71A91",
              "versionEndExcluding": "10.11.11",
              "versionStartIncluding": "10.11.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7F64C167-943D-4F3F-9374-BCC8DECB3881",
              "versionEndExcluding": "11.2.3",
              "versionStartIncluding": "11.2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "945A6E29-209F-4992-8692-BEF63DCB6B98",
              "versionEndExcluding": "11.3.1",
              "versionStartIncluding": "11.3.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Mattermost versions 11.3.x \u003c= 11.3.0, 11.2.x \u003c= 11.2.2, 10.11.x \u003c= 10.11.10 fail to canonicalize IPv4-mapped IPv6 addresses before reserved IP validation which allows an attacker to perform SSRF attacks against internal services via IPv4-mapped IPv6 literals (e.g., [::ffff:127.0.0.1]).. Mattermost Advisory ID: MMSA-2026-00585"
    },
    {
      "lang": "es",
      "value": "Las versiones de Mattermost 11.3.x \u0026lt;= 11.3.0, 11.2.x \u0026lt;= 11.2.2, 10.11.x \u0026lt;= 10.11.10 no logran canonicalizar las direcciones IPv6 mapeadas a IPv4 antes de la validaci\u00f3n de IP reservadas, lo que permite a un atacante realizar ataques SSRF contra servicios internos a trav\u00e9s de literales IPv6 mapeados a IPv4 (por ejemplo, [::ffff:127.0.0.1]).. ID de Aviso de Mattermost: MMSA-2026-00585"
    }
  ],
  "id": "CVE-2026-2455",
  "lastModified": "2026-06-17T10:30:59.067",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4,
        "source": "responsibledisclosure@mattermost.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-2455",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-03-16T18:37:36.914842Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-03-16T15:16:22.277",
  "references": [
    {
      "source": "responsibledisclosure@mattermost.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://mattermost.com/security-updates"
    }
  ],
  "sourceIdentifier": "responsibledisclosure@mattermost.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ],
      "source": "responsibledisclosure@mattermost.com",
      "type": "Secondary"
    }
  ]
}



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