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Medium

Open WebUI 0.6.31 before 0.11.4 Stored XSS via Tool-Call Embeds

Type: advisorySource: Official CVE List1 source record

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.

Announced Group revision 1
Original source ↗

CVE-2026-109300

Primary source · Revision 1

Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.

Security context

Source reference: cve:CVE-2026-109300

open-webui

Source reference: /containers/cna/affected/0/product

Affected versions
Not stated in this record
Fixed versions
Not stated in this record
Prerequisites
Not stated in this record

Structured affected-version data

Original package identities and version rules from this source.

[
  {
    "vendor": "open-webui",
    "product": "open-webui",
    "versions": [
      {
        "status": "affected",
        "version": "0.6.31",
        "lessThan": "0.11.4",
        "versionType": "semver"
      },
      {
        "status": "unaffected",
        "version": "0.11.4",
        "versionType": "semver"
      }
    ],
    "packageURL": "pkg:pypi/open-webui",
    "defaultStatus": "unaffected"
  }
]
Related CVEs
CVE-2026-109300

Source reference: /cveMetadata/cveId

Publisher severity

medium

Source reference: /containers/cna/metrics

Event
#20587 · Revision 1
Added to Heist Feed
Publisher date
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