CVE-2019-16781 [Medium] | XSS in Wordpress

In WordPress before 5.3.1, authenticated users with lower privileges (like contributors) can inject JavaScript code in the block editor, which is executed within the dashboard. It can lead to an admin opening the affected post in the editor leading to XSS.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	3.49%	1.40%	-2.09%
2	2026-03-04	5.00%	3.49%	-1.52%
3	2026-03-01	—	5.00%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

3.49%

1.40%

-2.09%

2026-03-04

5.00%

3.49%

-1.52%

2026-03-01

—

5.00%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.8	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/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:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. 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:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.	1.3	4.0	[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]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.8

3.1

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:N/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:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N): Data isn’t meaningfully altered or forged.
Availability (A:N): Service keeps running; no real outage angle.

1.3

4.0

[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]

OS Trackers for CVE-2019-16781

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2019-16781 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-2019-16781
`ubuntu`	medium	CVE-2019-16781 medium priority: Ubuntu including 1 source packages (wordpress), 18 status rows across 18 suites (bionic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 12, ignored 2, needs-triage 2, DNE 1, released 1.	https://ubuntu.com/security/CVE-2019-16781

Affected software / configurations for CVE-2019-16781

Vendor	Product	Version	Raw CPE
wordpress	wordpress	< 5.3.1	cpe:2.3:a:wordpress:wordpress::::::::
debian	debian_linux	9.0	cpe:2.3:o:debian:debian_linux:9.0:::::::*
debian	debian_linux	10.0	cpe:2.3:o:debian:debian_linux:10.0:::::::*

References for CVE-2019-16781

URL	Tags
https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-pg4x-64rh-3c9v	Third Party Advisory
https://hackerone.com/reports/731301	Permissions Required Third Party Advisory
https://seclists.org/bugtraq/2020/Jan/8	Mailing List Third Party Advisory
https://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/	Release Notes Third Party Advisory
https://wpvulndb.com/vulnerabilities/9976	Third Party Advisory
https://www.debian.org/security/2020/dsa-4599	Third Party Advisory
https://www.debian.org/security/2020/dsa-4677	Third Party Advisory

URL

CVE-2019-16781 | Stored cross-site scripting (XSS) in WordPress block editor

Exploit prediction scoring system (EPSS) score for CVE-2019-16781

Common vulnerability scoring system (CVSS) metrics for CVE-2019-16781

Weakness enumeration for CVE-2019-16781

OS Trackers for CVE-2019-16781

Affected software / configurations for CVE-2019-16781

References for CVE-2019-16781