HOMEVULNERABILITIESCVE-2019-20041
CRITICAL

CVE-2019-20041

CWE-20Published: December 27, 2019· Updated: Jun 17, 2026

9.8
CVSS v3.1

Official Description

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.

NVD Source

Technical Analysis

CVE-2019-20041 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

Debian1 product(s)
debian linux
WordPress1 product(s)
wordpress
Source: NVD CPE · 4 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://github.com/WordPress/wordpress-develop/commit/b1975463dd995da19bb40d3fa0786498717e3c53
PATCHhttps://github.com/WordPress/wordpress-develop/commit/b1975463dd995da19bb40d3fa0786498717e3c53
ADVISORYhttps://lists.debian.org/debian-lts-announce/2020/01/msg00010.html
ADVISORYhttps://seclists.org/bugtraq/2020/Jan/8
ADVISORYhttps://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/
ADVISORYhttps://www.debian.org/security/2020/dsa-4599
ADVISORYhttps://www.debian.org/security/2020/dsa-4677
ADVISORYhttps://lists.debian.org/debian-lts-announce/2020/01/msg00010.html
ADVISORYhttps://seclists.org/bugtraq/2020/Jan/8
ADVISORYhttps://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/
ADVISORYhttps://www.debian.org/security/2020/dsa-4599
ADVISORYhttps://www.debian.org/security/2020/dsa-4677

All References (12)

→
https://github.com/WordPress/wordpress-develop/commit/b1975463dd995da19bb40d3fa0786498717e3c53Patch
→
https://lists.debian.org/debian-lts-announce/2020/01/msg00010.htmlMailing List · Third Party Advisory
→
https://seclists.org/bugtraq/2020/Jan/8Mailing List · Third Party Advisory
→
https://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/Release Notes · Vendor Advisory
→
https://www.debian.org/security/2020/dsa-4599Third Party Advisory
→
https://www.debian.org/security/2020/dsa-4677Third Party Advisory
→
https://github.com/WordPress/wordpress-develop/commit/b1975463dd995da19bb40d3fa0786498717e3c53Patch
→
https://lists.debian.org/debian-lts-announce/2020/01/msg00010.htmlMailing List · Third Party Advisory
→
https://seclists.org/bugtraq/2020/Jan/8Mailing List · Third Party Advisory
→
https://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/Release Notes · Vendor Advisory
→
https://www.debian.org/security/2020/dsa-4599Third Party Advisory
→
https://www.debian.org/security/2020/dsa-4677Third Party Advisory

Quick Facts

CVE IDCVE-2019-20041
CVSS Score9.8 / 10
SeverityCRITICAL
WeaknessCWE-20
CISA KEVNo
Affected2 vendor(s)
PublishedDec 27, 2019

Related CVEs (CWE-20)

CVE-2007-6494
10.0
CVE-2008-1331
10.0
CVE-2024-22476
10.0
CVE-2026-34910
KEV10.0
CVE-2008-6826
10.0
CVE-2008-6555
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2019-20041 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.
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