CVE-2026-66829

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 1.5.3.
Configurations

Configuration 1 (hide)

cpe:2.3:a:rrrene:htmlsanitizeex:*:*:*:*:*:*:*:*

History

11 Aug 2026, 13:51

Type Values Removed Values Added
References () https://cna.erlef.org/cves/CVE-2026-66829.html - () https://cna.erlef.org/cves/CVE-2026-66829.html - Patch, Third Party Advisory
References () https://github.com/rrrene/html_sanitize_ex/commit/9f7e38be51edc38f132dfe994f37af5cf5e0e76f - () https://github.com/rrrene/html_sanitize_ex/commit/9f7e38be51edc38f132dfe994f37af5cf5e0e76f - Patch
References () https://github.com/rrrene/html_sanitize_ex/security/advisories/GHSA-2c6f-3j54-xpcr - () https://github.com/rrrene/html_sanitize_ex/security/advisories/GHSA-2c6f-3j54-xpcr - Broken Link
References () https://osv.dev/vulnerability/EEF-CVE-2026-66829 - () https://osv.dev/vulnerability/EEF-CVE-2026-66829 - Patch, Third Party Advisory
CPE cpe:2.3:a:rrrene:htmlsanitizeex:*:*:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 6.1
First Time Rrrene
Rrrene htmlsanitizeex

06 Aug 2026, 16:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-08-06 16:16

Updated : 2026-08-11 13:51


NVD link : CVE-2026-66829

Mitre link : CVE-2026-66829

CVE.ORG link : CVE-2026-66829


JSON object : View

Products Affected

rrrene

  • htmlsanitizeex
CWE
CWE-601

URL Redirection to Untrusted Site ('Open Redirect')