Improper input validation in Wordpress

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: substring.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.046 (90.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

  • cve@mitre.org (x_refsource_MISC, Release Notes, Vendor Advisory)
  • cve@mitre.org (Patch, x_refsource_MISC)
  • cve@mitre.org (mailing-list, x_refsource_BUGTRAQ, Mailing List, Third Party Advisory)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
  • cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)

Frequently asked questions

What is CVE-2019-20041?
CVE-2019-20041 is a critical-severity vulnerability in Wordpress, classified under Improper Input Validation. CVSS score: 9.8/10. Published 2019-12-27.
How severe is CVE-2019-20041?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2019-20041 known to be exploited?
8 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.