Vulnerability-Lookup

CERTFR-2026-AVI-0201

Vulnerability from certfr_avis - Published: 2026-02-24 - Updated: 2026-03-26

De multiples vulnérabilités ont été découvertes dans Mattermost Server. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service à distance, une injection de requêtes illégitimes par rebond (CSRF) et un contournement de la politique de sécurité.

Solutions

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

Impacted products

Vendor	Product	Description
Mattermost	Mattermost Server	Mattermost Server versions 10.11.x antérieures à 10.11.12
Mattermost	Mattermost Server	Mattermost Server versions 11.4.x antérieures à 11.4.1
Mattermost	Mattermost Server	Mattermost Server versions 11.3.x antérieures à 11.3.2
Mattermost	Mattermost Server	Mattermost Server versions 11.2.x antérieures à 11.2.4

References

Title

Publication Time

Tags

Bulletin de sécurité Mattermost MMSA-2026-00599	2026-02-24	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2025-00562	2026-02-24	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00598	2026-02-24	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00594	2026-02-24	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2025-00566	2026-02-23	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00578	2026-02-23	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00593	2026-02-24	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00590	2026-02-23	vendor-advisory
Bulletin de sécurité Mattermost MMSA-2026-00595	2026-02-23	vendor-advisory

Show details on source website

JSON

To clipboard

{
  "$ref": "https://www.cert.ssi.gouv.fr/openapi.json",
  "affected_systems": [
    {
      "description": "Mattermost Server versions 10.11.x ant\u00e9rieures \u00e0 10.11.12",
      "product": {
        "name": "Mattermost Server",
        "vendor": {
          "name": "Mattermost",
          "scada": false
        }
      }
    },
    {
      "description": "Mattermost Server versions 11.4.x ant\u00e9rieures \u00e0 11.4.1",
      "product": {
        "name": "Mattermost Server",
        "vendor": {
          "name": "Mattermost",
          "scada": false
        }
      }
    },
    {
      "description": "Mattermost Server versions 11.3.x ant\u00e9rieures \u00e0 11.3.2",
      "product": {
        "name": "Mattermost Server",
        "vendor": {
          "name": "Mattermost",
          "scada": false
        }
      }
    },
    {
      "description": "Mattermost Server versions 11.2.x ant\u00e9rieures \u00e0 11.2.4",
      "product": {
        "name": "Mattermost Server",
        "vendor": {
          "name": "Mattermost",
          "scada": false
        }
      }
    }
  ],
  "affected_systems_content": "",
  "content": "## Solutions\n\nSe r\u00e9f\u00e9rer au bulletin de s\u00e9curit\u00e9 de l\u0027\u00e9diteur pour l\u0027obtention des correctifs (cf. section Documentation).",
  "cves": [
    {
      "name": "CVE-2026-20719",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-20719"
    },
    {
      "name": "CVE-2026-27659",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-27659"
    },
    {
      "name": "CVE-2026-27656",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-27656"
    },
    {
      "name": "CVE-2026-26233",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-26233"
    }
  ],
  "initial_release_date": "2026-02-24T00:00:00",
  "last_revision_date": "2026-03-26T00:00:00",
  "links": [],
  "reference": "CERTFR-2026-AVI-0201",
  "revisions": [
    {
      "description": "Version initiale",
      "revision_date": "2026-02-24T00:00:00.000000"
    },
    {
      "description": "Ajout r\u00e9f\u00e9rences CVE",
      "revision_date": "2026-03-26T00:00:00.000000"
    }
  ],
  "risks": [
    {
      "description": "D\u00e9ni de service \u00e0 distance"
    },
    {
      "description": "Injection de requ\u00eates ill\u00e9gitimes par rebond (CSRF)"
    },
    {
      "description": "Non sp\u00e9cifi\u00e9 par l\u0027\u00e9diteur"
    },
    {
      "description": "Contournement de la politique de s\u00e9curit\u00e9"
    }
  ],
  "summary": "De multiples vuln\u00e9rabilit\u00e9s ont \u00e9t\u00e9 d\u00e9couvertes dans Mattermost Server. Certaines d\u0027entre elles permettent \u00e0 un attaquant de provoquer un d\u00e9ni de service \u00e0 distance, une injection de requ\u00eates ill\u00e9gitimes par rebond (CSRF) et un contournement de la politique de s\u00e9curit\u00e9.",
  "title": "Multiples vuln\u00e9rabilit\u00e9s dans Mattermost Server",
  "vendor_advisories": [
    {
      "published_at": "2026-02-24",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00599",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-24",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2025-00562",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-24",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00598",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-24",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00594",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-23",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2025-00566",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-23",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00578",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-24",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00593",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-23",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00590",
      "url": "https://mattermost.com/security-updates/"
    },
    {
      "published_at": "2026-02-23",
      "title": "Bulletin de s\u00e9curit\u00e9 Mattermost MMSA-2026-00595",
      "url": "https://mattermost.com/security-updates/"
    }
  ]
}

CVE-2026-27656 (GCVE-0-2026-27656)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:28 – Updated: 2026-03-26 13:19

Title

Account Takeover via Substring Matching in OpenID Connect Authentication

Summary

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to properly validate user identity in the OpenID {{IsSameUser()}} comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user discovery flow.. Mattermost Advisory ID: MMSA-2026-00590

Severity ?

5.7 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N

CWE

CWE-303 - Incorrect Implementation of Authentication Algorithm

Assigner

Mattermost

References

URL

Tags

https://mattermost.com/security-updates

vendor-advisory

Impacted products

	Vendor	Product	Version
	Mattermost	Mattermost	Affected: 11.4.0 , ≤ 11.4.0 (semver) Affected: 11.3.0 , ≤ 11.3.1 (semver) Affected: 11.2.0 , ≤ 11.2.3 (semver) Affected: 10.11.0 , ≤ 10.11.11 (semver) Unaffected: 11.5.0 Unaffected: 11.4.1 Unaffected: 11.3.2 Unaffected: 11.2.4 Unaffected: 10.11.12

Credits

Christopher Poile

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-27656",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-26T03:55:33.452102Z",
                "version": "2.0.3"
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            },
            {
              "lessThanOrEqual": "11.3.1",
              "status": "affected",
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              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "11.2.3",
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              "version": "10.11.0",
              "versionType": "semver"
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              "status": "unaffected",
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            },
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              "status": "unaffected",
              "version": "11.4.1"
            },
            {
              "status": "unaffected",
              "version": "11.3.2"
            },
            {
              "status": "unaffected",
              "version": "11.2.4"
            },
            {
              "status": "unaffected",
              "version": "10.11.12"
            }
          ]
        }
      ],
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          "type": "finder",
          "value": "Christopher Poile"
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      ],
      "descriptions": [
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          "value": "Mattermost versions 11.4.x \u003c= 11.4.0, 11.3.x \u003c= 11.3.1, 11.2.x \u003c= 11.2.3, 10.11.x \u003c= 10.11.11 fail to properly validate user identity in the OpenID {{IsSameUser()}} comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user discovery flow.. Mattermost Advisory ID: MMSA-2026-00590"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:H/A:N",
            "version": "3.1"
          },
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              "value": "GENERAL"
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          "descriptions": [
            {
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          "name": "MMSA-2026-00590",
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          ],
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.5.0, 11.4.1, 11.3.2, 11.2.4, 10.11.12 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2026-00590",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-67181"
        ],
        "discovery": "{\"self\"=\u003e\"https://mattermost.atlassian.net/rest/api/2/customFieldOption/10557\", \"value\"=\u003e\"Internal\", \"id\"=\u003e\"10557\"}"
      },
      "title": "Account Takeover via Substring Matching in OpenID Connect Authentication",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
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    "assignerShortName": "Mattermost",
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    "dateReserved": "2026-02-23T22:07:32.808Z",
    "dateUpdated": "2026-03-26T13:19:52.338Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-27659 (GCVE-0-2026-27659)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:33 – Updated: 2026-03-25 17:39

Title

CSRF vulnerability in UpdateAccessControlPolicyActiveStatus endpoint

Summary

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to properly validate CSRF tokens in the /api/v4/access_control_policies/{policy_id}/activate endpoint, which allows an attacker to trick an admin into changing access control policy active status via a crafted request.. Mattermost Advisory ID: MMSA-2026-00578

Severity ?

4.6 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N

CWE

CWE-352 - Cross-Site Request Forgery (CSRF)

Assigner

Mattermost

References

URL

Tags

https://mattermost.com/security-updates

vendor-advisory

Impacted products

	Vendor	Product	Version
	Mattermost	Mattermost	Affected: 11.2.0 , ≤ 11.2.2 (semver) Affected: 10.11.0 , ≤ 10.11.10 (semver) Affected: 11.4.0 , ≤ 11.4.0 (semver) Affected: 11.3.0 , ≤ 11.3.1 (semver) Unaffected: 11.5.0 Unaffected: 11.2.3 Unaffected: 10.11.11 Unaffected: 11.4.1 Unaffected: 11.3.2

Credits

Joshua Rogers

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-27659",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-25T17:39:20.789294Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-25T17:39:28.092Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
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          "product": "Mattermost",
          "vendor": "Mattermost",
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              "status": "affected",
              "version": "11.2.0",
              "versionType": "semver"
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              "lessThanOrEqual": "10.11.10",
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              "version": "10.11.0",
              "versionType": "semver"
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              "version": "11.4.0",
              "versionType": "semver"
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              "version": "11.5.0"
            },
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              "status": "unaffected",
              "version": "11.2.3"
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              "status": "unaffected",
              "version": "10.11.11"
            },
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              "status": "unaffected",
              "version": "11.4.1"
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              "status": "unaffected",
              "version": "11.3.2"
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      "credits": [
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          "lang": "en",
          "type": "finder",
          "value": "Joshua Rogers"
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          "lang": "en",
          "value": "Mattermost versions 11.2.x \u003c= 11.2.2, 10.11.x \u003c= 10.11.10, 11.4.x \u003c= 11.4.0, 11.3.x \u003c= 11.3.1 fail to properly validate CSRF tokens in the /api/v4/access_control_policies/{policy_id}/activate endpoint, which allows an attacker to trick an admin into changing access control policy active status via a crafted request.. Mattermost Advisory ID: MMSA-2026-00578"
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            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 4.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N",
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          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.5.0, 11.2.3, 10.11.11, 11.4.1, 11.3.2 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2026-00578",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-67125"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "CSRF vulnerability in UpdateAccessControlPolicyActiveStatus endpoint",
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    "datePublished": "2026-03-25T16:33:32.724Z",
    "dateReserved": "2026-02-23T22:18:41.203Z",
    "dateUpdated": "2026-03-25T17:39:28.092Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

CVE-2026-20719 (GCVE-0-2026-20719)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:30 – Updated: 2026-03-26 17:11

Title

DoS via URL Previews Rendering Malicious SVGs

Summary

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to prevent rendering of external SVGs on link embeds which allows unauthenticated users to crash the Mattermost webapp and desktop app via creating an issue or PR on GitHub.. Mattermost Advisory ID: MMSA-2026-00595

Severity ?

4.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CWE

CWE-754 - Improper Check for Unusual or Exceptional Conditions

Assigner

Mattermost

References

URL

Tags

https://mattermost.com/security-updates

vendor-advisory

Impacted products

	Vendor	Product	Version
	Mattermost	Mattermost	Affected: 11.4.0 , ≤ 11.4.0 (semver) Affected: 11.3.0 , ≤ 11.3.1 (semver) Affected: 11.2.0 , ≤ 11.2.3 (semver) Affected: 10.11.0 , ≤ 10.11.11 (semver) Unaffected: 11.5.0 Unaffected: 11.4.1 Unaffected: 11.3.2 Unaffected: 11.2.4 Unaffected: 10.11.12

Credits

mk7120

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20719",
                "options": [
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                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-26T17:11:15.846505Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
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          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "11.4.0",
              "status": "affected",
              "version": "11.4.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "11.3.1",
              "status": "affected",
              "version": "11.3.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "11.2.3",
              "status": "affected",
              "version": "11.2.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.11.11",
              "status": "affected",
              "version": "10.11.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "11.5.0"
            },
            {
              "status": "unaffected",
              "version": "11.4.1"
            },
            {
              "status": "unaffected",
              "version": "11.3.2"
            },
            {
              "status": "unaffected",
              "version": "11.2.4"
            },
            {
              "status": "unaffected",
              "version": "10.11.12"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "mk7120"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mattermost versions 11.4.x \u003c= 11.4.0, 11.3.x \u003c= 11.3.1, 11.2.x \u003c= 11.2.3, 10.11.x \u003c= 10.11.11 fail to prevent rendering of external SVGs on link embeds which allows unauthenticated users to crash the Mattermost webapp and desktop app via creating an issue or PR on GitHub.. Mattermost Advisory ID: MMSA-2026-00595"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 4.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
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          },
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              "lang": "en",
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            }
          ]
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      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-754",
              "description": "CWE-754: Improper Check for Unusual or Exceptional Conditions",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-25T16:30:47.041Z",
        "orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
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      },
      "references": [
        {
          "name": "MMSA-2026-00595",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.5.0, 11.4.1, 11.3.2, 11.2.4, 10.11.12 or higher."
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      ],
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        "advisory": "MMSA-2026-00595",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-67371"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "DoS via URL Previews Rendering Malicious SVGs",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
    "cveId": "CVE-2026-20719",
    "datePublished": "2026-03-25T16:30:47.041Z",
    "dateReserved": "2026-02-23T22:07:32.817Z",
    "dateUpdated": "2026-03-26T17:11:21.474Z",
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  },
  "dataType": "CVE_RECORD",
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CVE-2026-26233 (GCVE-0-2026-26233)

Vulnerability from cvelistv5 – Published: 2026-03-25 16:24 – Updated: 2026-03-27 14:59

Title

Denial of Service via HTTP/2 single packet attack on login endpoint

Summary

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to rate limit login requests which allows unauthenticated remote attackers to cause denial of service (server crash and restart) via HTTP/2 single packet attack with 100+ parallel login requests.. Mattermost Advisory ID: MMSA-2025-00566

Severity ?

4.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CWE

CWE-400 - Uncontrolled Resource Consumption

Assigner

Mattermost

References

URL

Tags

https://mattermost.com/security-updates

vendor-advisory

Impacted products

	Vendor	Product	Version
	Mattermost	Mattermost	Affected: 11.4.0 , ≤ 11.4.0 (semver) Affected: 11.3.0 , ≤ 11.3.1 (semver) Affected: 11.2.0 , ≤ 11.2.3 (semver) Affected: 10.11.0 , ≤ 10.11.11 (semver) Unaffected: 11.5.0 Unaffected: 11.4.1 Unaffected: 11.3.2 Unaffected: 11.2.4 Unaffected: 10.11.12

Credits

Axel Larsson & Jakob Ristner

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-26233",
                "options": [
                  {
                    "Exploitation": "none"
                  },
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                  },
                  {
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                "timestamp": "2026-03-27T14:59:40.444232Z",
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Tags

Taxonomy of the tags.

All sightings related to this event Export sightings related to this event

Sightings

Author	Source	Type	Date

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.

Action not permitted

CERTFR-2026-AVI-0201

Solutions

CVE-2026-27656 (GCVE-0-2026-27656)

CVE-2026-27659 (GCVE-0-2026-27659)

CVE-2026-20719 (GCVE-0-2026-20719)

CVE-2026-26233 (GCVE-0-2026-26233)

Tags

Sightings

Nomenclature