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        "cveId": "CVE-2026-109300",
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        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-10-12T14:13:39.026Z",
        "datePublished": "2026-10-12T16:04:58.200Z",
        "dateUpdated": "2026-10-12T16:04:58.200Z"
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                "dateUpdated": "2026-10-12T16:04:58.200Z"
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            "datePublic": "2026-09-27T00:00:00.000Z",
            "title": "Open WebUI 0.6.31 before 0.11.4 Stored XSS via Tool-Call Embeds",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Open WebUI from 0.6.31 before 0.11.4 contains a stored cross-site scripting vulnerability in its Markdown renderer, which treats user-authored tool-call details blocks as tool output and mounts their embeds attribute in script-enabled iframes. Authenticated users can post crafted channel messages, chat messages, or citation content that runs JavaScript in viewers' browsers, enabling in-app phishing, or session hijacking where iframeSandboxAllowSameOrigin is enabled."
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                    "descriptions": [
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                            "lang": "en",
                            "description": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
                            "cweId": "CWE-79",
                            "type": "CWE"
                        }
                    ]
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            "affected": [
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                    "vendor": "open-webui",
                    "product": "open-webui",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:pypi/open-webui",
                    "versions": [
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                            "version": "0.6.31",
                            "status": "affected",
                            "versionType": "semver",
                            "lessThan": "0.11.4"
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                            "version": "0.11.4",
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                            "versionType": "semver"
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                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "LOW",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "LOW",
                        "vulnIntegrityImpact": "LOW",
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                        "subConfidentialityImpact": "NONE",
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                        "scope": "UNCHANGED",
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            "references": [
                {
                    "url": "https://github.com/open-webui/open-webui/security/advisories/GHSA-9wj4-mcm3-ppj6",
                    "tags": [
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                    "name": "GitHub Security Advisory (GHSA-9wj4-mcm3-ppj6)"
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