CVE-2021-39201 | Authenticated cross-site scripting (XSS) in WordPress editor

WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. ### Impact The issue allows an authenticated but low-privileged user (like contributor/author) to execute XSS in the editor. This bypasses the restrictions imposed on users who do not have the permission to post `unfiltered_html`. ### Patches This has been patched in WordPress 5.8, and will be pushed to older versions via minor releases (automatic updates). It's strongly recommended that you keep auto-updates enabled to receive the fix. ### References https://wordpress.org/news/category/releases/ https://hackerone.com/reports/1142140 ### For more information If you have any questions or comments about this advisory: * Open an issue in [HackerOne](https://hackerone.com/wordpress)

Published: 2021-09-09 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-39201 is rated Moderate Risk (56.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.50%). 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-2021-39201

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 0.51% 1.50% +0.99%
2 2026-03-04 0.43% 0.51% +0.08%
3 2026-03-01 0.43%

Full EPSS history (43 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-39201

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/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:H)
Serious risk that confidential data gets exposed in a big way.
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 4.7 [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-2021-39201

OS Trackers for CVE-2021-39201

vendor priority summary link
debian not yet assigned CVE-2021-39201 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-2021-39201
ubuntu low CVE-2021-39201 low priority: Ubuntu including 1 source packages (wordpress), 15 status rows across 15 suites (bionic, focal, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 7, needs-triage 7, DNE 1. https://ubuntu.com/security/CVE-2021-39201

Affected software / configurations for CVE-2021-39201

Vendor Product Version Raw CPE
wordpress wordpress >= 5.0, < 5.8 cpe:2.3:a:wordpress:wordpress:*:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

References for CVE-2021-39201

cvelogic Threat Intelligence