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CVE-2019-20041: wp_kses_bad_protocol in wp-includes/kses.php in WordPress before 5.3.1 mishandles the HTML5 colon named entity, allowing attackers to bypass input sanitization, as demonstrated by the javascript&colon

critical Affects WordPress core. Feed 2026.10.29.1, updated 2026-10-28; published ; advisory modified .

wp_kses_bad_protocol in wp-includes/kses.php in WordPress before 5.3.1 mishandles the HTML5 colon named entity, allowing attackers to bypass input sanitization, as demonstrated by the javascript&colon

Package
WordPress core WordPress
Affected versions
<5.3.1
Fixed in
5.3.1
Severity
critical  CVSS 9.8
Exploitation
not on CISA KEV · EPSS 5% (91.5th percentile)
Published
2019-12-27
Source
nvd

References

CWE-20
NVD recordWordPress core advisories

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