CVE-2026-63205 (GCVE-0-2026-63205)

Vulnerability from cvelistv5 – Published: 2026-09-25 18:13 – Updated: 2026-09-25 18:13
VLAI
Title
Zammad: Channel admins can read unauthorized attachments via signature rich-text body
Summary
Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when creating or updating an email signature, Zammad processes inline images referenced in the signature body. If a signature body contains an HTML img tag pointing to any existing attachment, the system copies that attachment into a new signature-owned record, without checking whether the user has permission to access the original attachment. The newly created copy is then downloadable by the same channel-admin user, because attachment access is determined by the copy's owner (the signature), not the original object (e.g., a ticket or knowledge-base article). This allows a user with any of the admin.channel_email, admin.channel_google, admin.channel_microsoft365, or admin.channel_microsoft_graph permissions to read attachments they would otherwise be denied access to, such as ticket attachments belonging to groups they are not a member of. This issue is fixed in version 7.1.2.
Severity
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-862 - Missing Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
zammad zammad Affected: < 7.1.2
guessed Create a notification for this product.
Show details on NVD website
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{
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          "vendor": "zammad",
          "versions": [
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          "value": "Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when creating or updating an email signature, Zammad processes inline images referenced in the signature body. If a signature body contains an HTML img tag pointing to any existing attachment, the system copies that attachment into a new signature-owned record, without checking whether the user has permission to access the original attachment. The newly created copy is then downloadable by the same channel-admin user, because attachment access is determined by the copy\u0027s owner (the signature), not the original object (e.g., a ticket or knowledge-base article). This allows a user with any of the admin.channel_email, admin.channel_google, admin.channel_microsoft365, or admin.channel_microsoft_graph permissions to read attachments they would otherwise be denied access to, such as ticket attachments belonging to groups they are not a member of. This issue is fixed in version 7.1.2."
        }
      ],
      "metrics": [
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            "attackRequirements": "NONE",
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            "baseScore": 5.1,
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            "privilegesRequired": "HIGH",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
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              "description": "CWE-639: Authorization Bypass Through User-Controlled Key",
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              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
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              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
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      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-25T18:13:25.176Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
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          "name": "https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5"
        },
        {
          "name": "https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44",
          "tags": [
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          ],
          "url": "https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44"
        }
      ],
      "source": {
        "advisory": "GHSA-pp8r-x7pp-5qj5",
        "discovery": "UNKNOWN"
      },
      "title": "Zammad: Channel admins can read unauthorized attachments via signature rich-text body"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-63205",
    "datePublished": "2026-09-25T18:13:25.176Z",
    "dateReserved": "2026-07-15T22:19:06.906Z",
    "dateUpdated": "2026-09-25T18:13:25.176Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
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      "date": "2026-09-28",
      "epss": "0.00321",
      "percentile": "0.22598"
    },
    "nvd": {
      "cve": {
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                "product": "zammad",
                "vendor": "zammad",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003c 7.1.2"
                  }
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            "source": "security-advisories@github.com"
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        "cveTags": [],
        "descriptions": [
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            "lang": "en",
            "value": "Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when creating or updating an email signature, Zammad processes inline images referenced in the signature body. If a signature body contains an HTML img tag pointing to any existing attachment, the system copies that attachment into a new signature-owned record, without checking whether the user has permission to access the original attachment. The newly created copy is then downloadable by the same channel-admin user, because attachment access is determined by the copy\u0027s owner (the signature), not the original object (e.g., a ticket or knowledge-base article). This allows a user with any of the admin.channel_email, admin.channel_google, admin.channel_microsoft365, or admin.channel_microsoft_graph permissions to read attachments they would otherwise be denied access to, such as ticket attachments belonging to groups they are not a member of. This issue is fixed in version 7.1.2."
          }
        ],
        "id": "CVE-2026-63205",
        "lastModified": "2026-09-28T14:45:39.697",
        "metrics": {
          "cvssMetricV40": [
            {
              "cvssData": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
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                "availabilityRequirement": "NOT_DEFINED",
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                "baseSeverity": "MEDIUM",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "HIGH",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
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                "vulnIntegrityImpact": "NONE",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
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          }
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      }
    }
  }
}



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