FKIE_CVE-2026-28788

Vulnerability from fkie_nvd - Published: 2026-03-27 00:16 - Updated: 2026-04-01 16:12
Severity ?
7.1 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to version 0.8.6, any authenticated user can overwrite any file's content by ID through the `POST /api/v1/retrieval/process/files/batch` endpoint. The endpoint performs no ownership check, so a regular user with read access to a shared knowledge base can obtain file UUIDs via `GET /api/v1/knowledge/{id}/files` and then overwrite those files, escalating from read to write. The overwritten content is served to the LLM via RAG, meaning the attacker controls what the model tells other users. Version 0.8.6 patches the issue.
References
security-advisories@github.comhttps://github.com/open-webui/open-webui/security/advisories/GHSA-jjp7-g2jw-wh3jExploit, Vendor Advisory
Impacted products
Vendor Product Version
openwebui open_webui *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "98042D01-E16B-45CE-9BBC-E5A6E2AA2370",
              "versionEndExcluding": "0.8.6",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to version 0.8.6, any authenticated user can overwrite any file\u0027s content by ID through the `POST /api/v1/retrieval/process/files/batch` endpoint. The endpoint performs no ownership check, so a regular user with read access to a shared knowledge base can obtain file UUIDs via `GET /api/v1/knowledge/{id}/files` and then overwrite those files, escalating from read to write. The overwritten content is served to the LLM via RAG, meaning the attacker controls what the model tells other users. Version 0.8.6 patches the issue."
    },
    {
      "lang": "es",
      "value": "Open WebUI es una plataforma de inteligencia artificial autoalojada dise\u00f1ada para operar completamente sin conexi\u00f3n. Antes de la versi\u00f3n 0.8.6, cualquier usuario autenticado puede sobrescribir el contenido de cualquier archivo por ID a trav\u00e9s del endpoint \u0027POST /api/v1/retrieval/process/files/batch\u0027. El endpoint no realiza ninguna verificaci\u00f3n de propiedad, por lo que un usuario regular con acceso de lectura a una base de conocimiento compartida puede obtener los UUID de los archivos a trav\u00e9s de \u0027GET /api/v1/knowledge/{id}/files\u0027 y luego sobrescribir esos archivos, escalando de lectura a escritura. El contenido sobrescrito se sirve al LLM a trav\u00e9s de RAG, lo que significa que el atacante controla lo que el modelo dice a otros usuarios. La versi\u00f3n 0.8.6 corrige el problema."
    }
  ],
  "id": "CVE-2026-28788",
  "lastModified": "2026-04-01T16:12:25.257",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 7.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-27T00:16:22.673",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-jjp7-g2jw-wh3j"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-639"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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