WordPress <= 5.3 - Authenticated Stored XSS via Block Editor Content



Description
WordPress users with lower privileges (like contributors) can inject JavaScript code in the block editor using a specific payload, which is executed within the dashboard. This can lead to XSS if an admin opens the post in the editor. Execution of this attack does require an authenticated user.

Affects WordPresses

fixed in version 5.3.1
fixed in version 5.2.5
fixed in version 5.2.5
fixed in version 5.2.5
fixed in version 5.2.5
fixed in version 5.2.5
fixed in version 5.1.4
fixed in version 5.1.4
fixed in version 5.1.4
fixed in version 5.1.4
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 5.0.8
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.9.13
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.8.12
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.7.16
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.6.17
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.5.20
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.4.21
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.3.22
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.2.26
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.1.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 4.0.29
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.9.30
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.8.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32
fixed in version 3.7.32

References

CVE 2019-16781
CVE 2019-16780
URL https://wordpress.org/news/2019/12/wordpress-5-3-1-security-and-maintenance-release/
URL https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-pg4x-64rh-3c9v

Classification

Type XSS
OWASP Top 10 A7: Cross-Site Scripting (XSS)
CWE CWE-79

Miscellaneous

Original Researcher Nguyen The Duc
Submitter ducnt
Submitter Website http://www.ducnt.net/
Submitter Twitter https://twitter.com/ducnt_
Views 212715
Verified No
WPVDB ID 9976

Timeline

Publicly Published 2019-12-13 (7 months ago)
Added 2019-12-13 (7 months ago)
Last Updated 2020-05-01 (2 months ago)

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