CVE-2026-45398 (GCVE-0-2026-45398)

Vulnerability from cvelistv5 – Published: 2026-05-15 20:35 – Updated: 2026-05-19 03:55
VLAI
Title
Open WebUI: IDOR - Retrieval API Bypasses Knowledge Base Access Controls
Summary
Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user's knowledge base. This vulnerability is fixed in 0.9.5.
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
Impacted products
Vendor Product Version
open-webui open-webui Affected: < 0.9.5
Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-45398",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-18T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-19T03:55:35.975Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "open-webui",
          "vendor": "open-webui",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.9.5"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user\u0027s knowledge base. This vulnerability is fixed in 0.9.5."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-639",
              "description": "CWE-639: Authorization Bypass Through User-Controlled Key",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-15T20:35:35.482Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9"
        },
        {
          "name": "https://github.com/open-webui/open-webui/pull/22109",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-webui/open-webui/pull/22109"
        },
        {
          "name": "https://github.com/open-webui/open-webui/releases/tag/v0.9.5",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/open-webui/open-webui/releases/tag/v0.9.5"
        }
      ],
      "source": {
        "advisory": "GHSA-4g37-7p2c-38r9",
        "discovery": "UNKNOWN"
      },
      "title": "Open WebUI: IDOR - Retrieval API Bypasses Knowledge Base Access Controls"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-45398",
    "datePublished": "2026-05-15T20:35:35.482Z",
    "dateReserved": "2026-05-12T01:48:40.451Z",
    "dateUpdated": "2026-05-19T03:55:35.975Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-45398",
      "date": "2026-05-28",
      "epss": "0.00043",
      "percentile": "0.13399"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-45398\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-05-15T21:16:37.863\",\"lastModified\":\"2026-05-19T12:18:19.193\",\"vulnStatus\":\"Analyzed\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user\u0027s knowledge base. This vulnerability is fixed in 0.9.5.\"}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.5,\"baseSeverity\":\"HIGH\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"HIGH\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.6,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-639\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:a:openwebui:open_webui:*:*:*:*:*:*:*:*\",\"versionEndExcluding\":\"0.9.5\",\"matchCriteriaId\":\"19F64B41-71DA-4E31-A040-1C351A537567\"}]}]}],\"references\":[{\"url\":\"https://github.com/open-webui/open-webui/pull/22109\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Issue Tracking\",\"Patch\"]},{\"url\":\"https://github.com/open-webui/open-webui/releases/tag/v0.9.5\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Release Notes\"]},{\"url\":\"https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9\",\"source\":\"security-advisories@github.com\",\"tags\":[\"Exploit\",\"Mitigation\",\"Vendor Advisory\"]},{\"url\":\"https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"tags\":[\"Exploit\",\"Mitigation\",\"Vendor Advisory\"]}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-45398\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-05-18T16:01:45.264814Z\"}}}], \"references\": [{\"url\": \"https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-05-18T16:01:27.587Z\"}}], \"cna\": {\"title\": \"Open WebUI: IDOR - Retrieval API Bypasses Knowledge Base Access Controls\", \"source\": {\"advisory\": \"GHSA-4g37-7p2c-38r9\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 7.5, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"open-webui\", \"product\": \"open-webui\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 0.9.5\"}]}], \"references\": [{\"url\": \"https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9\", \"name\": \"https://github.com/open-webui/open-webui/security/advisories/GHSA-4g37-7p2c-38r9\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/open-webui/open-webui/pull/22109\", \"name\": \"https://github.com/open-webui/open-webui/pull/22109\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/open-webui/open-webui/releases/tag/v0.9.5\", \"name\": \"https://github.com/open-webui/open-webui/releases/tag/v0.9.5\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Open WebUI is a self-hosted artificial intelligence platform designed to operate entirely offline. Prior to 0.9.5, _validate_collection_access() checks the user-memory-* and file-* collection name prefixes but does not check knowledge base collections, which use raw UUIDs as collection names. Any authenticated user who knows a private knowledge base UUID can read its content through the retrieval query endpoints, even though the knowledge API correctly denies that user access. The same gap affects the retrieval write endpoints (/process/text, /process/file, /process/files/batch, /process/web, /process/youtube), allowing an attacker to inject content into or overwrite another user\u0027s knowledge base. This vulnerability is fixed in 0.9.5.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-639\", \"description\": \"CWE-639: Authorization Bypass Through User-Controlled Key\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-05-15T20:35:35.482Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-45398\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-05-19T03:55:35.975Z\", \"dateReserved\": \"2026-05-12T01:48:40.451Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-05-15T20:35:35.482Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…