---
id: "CVE-2026-112867"
kind: "vulnerability"
aliases: ["CVE-2026-112867"]
title: "H5P: stored cross-site scripting through unsanitized input up to 1.17.9"
severity: "medium"
cvss: 6.5
epss: 0.0013
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["cms", "h5p", "package", "self-hosted", "wordpress"]
not_affected_if: ["h5p-not-installed", "trusted-authors-only"]
published_at: "2026-10-22T07:16:41+00:00"
first_seen_at: "2026-10-23T21:57:30+00:00"
updated_at: "2026-10-25T03:47:34+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-112867", "first_seen_at": "2026-10-23T21:57:30+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-112867", "first_seen_at": "2026-10-24T07:15:52+00:00"}]
---

# H5P: stored cross-site scripting through unsanitized input up to 1.17.9

H5P versions up to and including 1.17.9 fail to neutralize input when generating web pages, enabling stored cross-site scripting. An attacker who can store crafted content can run JavaScript in the browser of users who view it.

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

## How to check

- Check the installed H5P plugin or library version against `1.17.9`
- Look at the H5P package version in the project's dependency or plugin manifest, if one is used

## Fix

- Upgrade H5P to a version later than `1.17.9`; the sources do not name the fixed release
- Until patched, restrict who can create or edit H5P content

## Timeline

- 2026-10-23T21:57:30+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-112867
- 2026-10-24T07:15:52+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-112867

## From the sources

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in H5P H5P h5p allows Stored XSS.This issue affects H5P: from n/a through 1.17.9.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_