CVE-2020-4046 | Authenticated XSS through embed block in WordPress

In affected versions of WordPress, users with low privileges (like contributors and authors) can use the embed block in a certain way to inject unfiltered HTML in the block editor. When affected posts are viewed by a higher privileged user, this could lead to script execution in the editor/wp-admin. This has been patched in version 5.4.2, along with all the previously affected versions via a minor release (5.3.4, 5.2.7, 5.1.6, 5.0.10, 4.9.15, 4.8.14, 4.7.18, 4.6.19, 4.5.22, 4.4.23, 4.3.24, 4.2.28, 4.1.31, 4.0.31, 3.9.32, 3.8.34, 3.7.34).

Published: 2020-06-12 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-4046 is rated Moderate Risk (45.6/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 2.36%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-4046

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 6.85% 2.36% -4.50%
2 2026-03-04 7.33% 6.85% -0.47%
3 2026-03-01 7.33%

Full EPSS history (42 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-4046

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.3 2.7 [email protected]
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.3 2.7 [email protected]
3.5 2.0 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
6.8 2.9 [email protected]

Weakness enumeration for CVE-2020-4046

OS Trackers for CVE-2020-4046

vendor priority summary link
debian not yet assigned CVE-2020-4046 not yet assigned priority: Debian including 1 source packages (wordpress), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-4046
ubuntu medium CVE-2020-4046 medium priority: Ubuntu including 1 source packages (wordpress), 17 status rows across 17 suites (bionic, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 6, ignored 5, needs-triage 4, DNE 1, released 1. https://ubuntu.com/security/CVE-2020-4046

Affected software / configurations for CVE-2020-4046

Vendor Product Version Raw CPE
wordpress wordpress >= 3.7, < 3.7.34 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 3.8, < 3.8.34 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 3.9, < 3.9.32 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.0, < 4.0.31 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.1, < 4.1.31 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.2, < 4.2.28 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.3, < 4.3.24 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.4, < 4.4.23 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.5, < 4.5.22 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.6, < 4.6.19 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.7, < 4.7.18 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.8, < 4.8.14 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 4.9, < 4.9.15 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 5.0, < 5.0.10 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 5.1, < 5.1.6 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 5.2, < 5.2.7 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 5.3.0, < 5.3.4 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
wordpress wordpress >= 5.4, < 5.4.2 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
fedoraproject fedora 31 cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*
fedoraproject fedora 32 cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*

References for CVE-2020-4046

cvelogic Threat Intelligence