---
id: CVE-2026-113661
aliases:
  - GHSA-cv27-6wvh-8x7j
title: >-
  ApostropheCMS: Incomplete CVE-2026-53606: `meta http-equiv=refresh` `content`
  still ships `javascript:` / `data:` URLs
summary: >-
  ApostropheCMS: Incomplete CVE-2026-53606: `meta http-equiv=refresh` `content`
  still ships `javascript:` / `data:` URLs
severity: medium
cvss: 5.4
cwe:
  - CWE-79
vendor: sanitize-html
product: sanitize-html
ecosystem: npm
affected:
  - sanitize-html < 2.18.0
patched:
  - sanitize-html 2.18.0
published: '2026-10-20'
updated: '2026-10-20'
sourceUpdated: '2026-10-20T18:15:34Z'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-cv27-6wvh-8x7j'
references:
  - url: >-
      https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-cv27-6wvh-8x7j
  - url: >-
      https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce
  - url: >-
      https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350
  - url: >-
      https://github.com/apostrophecms/apostrophe/releases/tag/sanitize-html@2.18.0
  - url: 'https://github.com/advisories/GHSA-cv27-6wvh-8x7j'
tags:
  - ghsa
  - npm
  - cve.org
ingestedAt: '2026-10-20T18:14:37.222Z'
---

## Overview

### Summary

CVE-2026-53606 expanded `allowedSchemesAppliedToAttributes` so named URL attributes (`action`, `formaction`, `data`, `poster`, `background`, later `ping`, `xlink:href`, …) go through `naughtyHref()`. A **URL nested inside `meta` `content`** (`http-equiv=refresh`) is not an attribute name on that list, so the embedded destination is never scheme-checked.

Default `allowedTags` still omit `meta`. Same non-default integrator config as 53606: allow `meta` plus `http-equiv` / `content`.

On **2.17.7**:

```text
sanitizeHtml(
  '<meta http-equiv="refresh" content="0;url=javascript:alert(1)">',
  { allowedTags: ['meta'], allowedAttributes: { meta: ['http-equiv', 'content'] } }
)
// => <meta http-equiv="refresh" content="0;url=javascript:alert(1)" />
```

`data:text/html,…` and arbitrary `https:` destinations also survive. `formaction="javascript:…"` (53606) is stripped.

Please **Request CVE**. Credit: Finder + Reporter (`adrbogacz`).

### Details

`naughtyHref()` only runs when the attribute name is in `allowedSchemesAppliedToAttributes` (`index.js` ~385). Refresh URLs live in a `content` value of the form `0;url=…`, so the gate never fires. Adding `content` to that list wholesale would break ordinary meta `content` (description, viewport).

**Fix:** when `http-equiv` is `refresh` (case-insensitive), parse the `; url=` destination and run `naughtyHref('meta', url)`. Drop `content` (or the tag) if the URL is rejected. Leave other `meta` `content` values alone.

### PoC

Local `sanitize-html@2.17.7`. Output inspection only:

```text
node -e '
const sanitize = require("sanitize-html");
const opts = { allowedTags: ["meta"], allowedAttributes: { meta: ["http-equiv", "content"] } };
for (const html of [
  "<meta http-equiv=\"refresh\" content=\"0;url=javascript:alert(1)\">",
  "<meta http-equiv=\"refresh\" content=\"0;url=data:text/html,aaa\">",
  "<form><button formaction=\"javascript:alert(1)\">x</button></form>",
]) {
  console.log(html, "=>", sanitize(html, html.includes("meta") ? opts : { allowedTags: ["form","button"], allowedAttributes: { button: ["formaction"] } }));
}
'
```

Expected: refresh `javascript:` / `data:` remain; 53606 `formaction` is removed. Do not attach a browser hang or stored-XSS page.

### Impact

An integrator who allowed `meta` + `content` expecting `allowedSchemes` to apply (the 53606 configuration pattern) still emits a refresh to `javascript:`, `data:`, or an attacker `https:` URL. Stored XSS / open redirect for viewers of that HTML. Default config is not affected.

## Affected packages

- `sanitize-html < 2.18.0`

## Remediation

Upgrade to a patched release:

- `sanitize-html 2.18.0`