CVE-2026-66829
NVD: 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... NVD: HtmlSanitizeEx.html5/1 keeps attacker-supplied <meta> elements in its output. NVD: 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.
2.3 Severity
LOW EPSS
0.0050 (40) KEV
-
Source-published summary
NVD: 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... NVD: HtmlSanitizeEx.html5/1 keeps attacker-supplied <meta> elements in its output. NVD: 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.
Possible impact
Source describes XSS risk · remote exposure. Possible impact: This low severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for XSS risk · remote exposure.
Affected context
vendor/product: rrrene / htmlsanitizeex
Remediation / advisory
Remediation reference present; patch status requires confirmation in the linked advisory.
Why it matters
Source describes XSS risk · remote exposure. Possible impact: This low severity issue needs human triage to confirm exposure, affected versions, and vendor guidance for XSS risk · remote exposure.; CVSS 2.3 (LOW); EPSS percentile 40; not listed in KEV; Remediation reference present; patch status requires confirmation in the linked advisory; sources: NVD, OSV.
What to verify
Confirm affected product/version, vendor advisory, patch or mitigation, and exposure.
Exposure hint
remote exposure
Impact tags
Urgency reasons
Source-derived note
Summary derived from NVD / OSV description; unsafe procedural detail is not shown.
Redaction metadata
- source summary used
- True
- fallback summary used
- False
- unsafe procedural detail present
- false
- raw source displayed
- false
- public summary redacted
- true
Remediation handoff
Public-safe static handoff for human/Codex remediation planning. Scan, patch, external execution, and auto remediation are disabled.
Safety note
This radar shows source-published defensive context only. Exploit procedures, exploit strings, scanner commands, and auto-remediation are not provided.
Official references
- https://nvd.nist.gov/vuln/detail/CVE-2026-66829
- https://osv.dev/vulnerability/CVE-2026-66829
- https://cna.erlef.org/cves/CVE-2026-66829.html
- https://github.com/rrrene/html_sanitize_ex/commit/9f7e38be51edc38f132dfe994f37af5cf5e0e76f
- https://github.com/rrrene/html_sanitize_ex/security/advisories/GHSA-2c6f-3j54-xpcr
- https://osv.dev/vulnerability/EEF-CVE-2026-66829