CVE-2026-66829: html_sanitize_ex HTML5 scrubber keeps attacker-supplied meta refresh, allowing forced cross-origin redirection
rrrene · html_sanitize_ex
Vendor fix available · Affected: rrrene html_sanitize_ex · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 47% of scored CVEs
DescriptionCVE.org
URL Redirection to Untrusted Site ('Open Redirect') vulnerability in the HTML5 scrubber in rrrene html_sanitize_ex allows a remote attacker to force visitors of a page to navigate to a site of the attacker's choosing via a <meta http-equiv="refresh"> element in sanitized HTML. HtmlSanitizeEx.html5/1 keeps attacker-supplied <meta> elements in its output. A meta element acts on the whole document rather than on the fragment it was embedded in, so it can also declare document-wide directives such as Content-Security-Policy. This is not cross-site scripting. Browsers do not navigate a meta refresh to a javascript: URL, so the uppercase JAVASCRIPT: filter bypass yields no script execution and none was demonstrated. This issue affects html_sanitize_ex: from 0.3.1 before 1.4.5 and from 1.5.0-rc.0 before 1.5.3.
Affected products2
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- rrrene · html_sanitize_exfrom 0.3.1 before 1.4.5; from 1.5.0-rc.0 before 1.5.3
- rrrene · html_sanitize_exVersions not stated
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Weakness
- Open Redirect
- Vendor
- rrrene
- Published
- August 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-66829 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.