CVE-2026-84463 (GCVE-0-2026-84463)

Vulnerability from cvelistv5 – Published: 2026-09-25 18:19 – Updated: 2026-09-25 18:19
VLAI
Title
Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute
Summary
Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, a user with Knowledge Base editing rights for a category can embed a video widget in a published answer with a specially crafted value. When the answer is rendered, that value is inserted into the page's HTML without being escaped for its attribute context, allowing it to break out and inject additional HTML into the page. When another user who has permission to switch between user sessions views the affected answer, the injected HTML causes their browser to silently send a request to Zammad's session-switching endpoint using their own active credentials. This results in switching their session to an account chosen by the person who wrote the Knowledge Base answer. No action is required from the viewer beyond opening the published answer. This issue is fixed in version 7.1.2.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-352 - Cross-Site Request Forgery (CSRF)
  • CWE-838 - Inappropriate Encoding for Output Context
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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        },
        {
          "descriptions": [
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      "providerMetadata": {
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          "name": "https://github.com/zammad/zammad/security/advisories/GHSA-cxjg-4gmf-5xqc",
          "tags": [
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          "url": "https://github.com/zammad/zammad/security/advisories/GHSA-cxjg-4gmf-5xqc"
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          "url": "https://github.com/zammad/zammad/commit/f7a97ea209696bce85ed62901ee753b88368851c"
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        "advisory": "GHSA-cxjg-4gmf-5xqc",
        "discovery": "UNKNOWN"
      },
      "title": "Zammad: Stored HTML injection in Knowledge Base video widget enables forced session switching via unescaped iframe attribute"
    }
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  "cveMetadata": {
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    "cveId": "CVE-2026-84463",
    "datePublished": "2026-09-25T18:19:19.193Z",
    "dateReserved": "2026-09-01T20:05:09.424Z",
    "dateUpdated": "2026-09-25T18:19:19.193Z",
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                    "version": "\u003c 7.1.2"
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          }
        ],
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                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
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                "providerUrgency": "NOT_DEFINED",
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}



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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.