---
id: "CVE-2026-126814"
page: "https://infrastack.ai/live/CVE-2026-126814"
kind: "vulnerability"
aliases: ["CVE-2026-126814"]
title: "blueprintUE Self-Hosted: iframe injection lets logged-in users frame phishing pages"
severity: "medium"
cvss: 4.8
epss: null
exploited: false
status: "open"
category: "other"
products: [{"name": "blueprintUE Self-Hosted Edition", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["blueprintue", "iframe", "other", "self-hosted"]
not_affected_if: ["no-authenticated-user-access", "version-4.3.6-or-later"]
published_at: "2026-11-11T21:16:46+00:00"
first_seen_at: "2026-11-11T21:29:09+00:00"
updated_at: "2026-11-11T21:31:02+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126814", "first_seen_at": "2026-11-11T21:29:09+00:00"}]
exploit_sources: []
---

# blueprintUE Self-Hosted: iframe injection lets logged-in users frame phishing pages

Link for people: https://infrastack.ai/live/CVE-2026-126814 (this .md is for agents)

blueprintUE Self-Hosted Edition before 4.3.6 lets an authenticated user embed arbitrary third-party content through a flawed PeerTube video URL matcher in BlueprintService::findVideoProvider(). An attacker can host a blueprint video URL on their own server, and site.js loads it in an unsandboxed iframe after consent, so fake login forms or malware downloads can appear inside the site.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:blueprintUE Self-Hosted Edition affected range not listed fixed no fixed version listed

## How to check

- Check the installed blueprintUE Self-Hosted Edition version and confirm it is at or above `4.3.6`.

## Fix

- blueprintUE Self-Hosted Edition: upgrade to `4.3.6`.

## Timeline

- 2026-11-11T21:29:09+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126814

## Documents

- [advisory] Vendor advisory: github.com https://github.com/blueprintue/blueprintue-self-hosted-edition/security/advisories/GHSA-3vgc-fcfg-v233
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/blueprintue-self-hosted-edition-before-4.3.6-arbitrary-iframe-embedding-via-peertube-matcher
- [fix] Patch: github.com https://github.com/blueprintue/blueprintue-self-hosted-edition/commit/5f13e2bb8cd4c620899e9f8afd41a6e62b3bc6a4
- [fix] Release notes: github.com https://github.com/blueprintue/blueprintue-self-hosted-edition/releases/tag/v4.3.6

## From the sources

blueprintUE Self-Hosted Edition before 4.3.6 contains an iframe injection vulnerability that allows authenticated users to embed arbitrary third-party content by abusing the PeerTube video URL matcher in BlueprintService::findVideoProvider(). Attackers can set a blueprint video URL on an attacker-controlled host, which site.js loads in an unsandboxed iframe after consent, framing fake login forms or malware downloads.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_