CVE-2020-4049: Authenticated self-XSS via theme uploads in WordPress

Published Jun 12, 2020
·
Updated

In affected versions of WordPress, when uploading themes, the name of the theme folder can be crafted in a way that could lead to JavaScript execution in /wp-admin on the themes page. This does require an admin to upload the theme, and is low severity self-XSS. 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).

Affected Software

24 affected componentsFixes available
debian/wordpress
5.0.15+dfsg1-0+deb10u15.0.19+dfsg1-0+deb10u15.7.8+dfsg1-0+deb11u26.1.1+dfsg1-16.3.1+dfsg1-1
WordPress WordPress>=3.7<3.7.34
WordPress WordPress>=3.8<3.8.34
WordPress WordPress>=3.9<3.9.32
WordPress WordPress>=4.0<4.0.31
WordPress WordPress>=4.1<4.1.31
WordPress WordPress>=4.2<4.2.28
WordPress WordPress>=4.3<4.3.24
WordPress WordPress>=4.4<4.4.23
WordPress WordPress>=4.5<4.5.22
WordPress WordPress>=4.6<4.6.19
WordPress WordPress>=4.7<4.7.18
WordPress WordPress>=4.8<4.8.14
WordPress WordPress>=4.9<4.9.15
WordPress WordPress>=5.0<5.0.10
WordPress WordPress>=5.1<5.1.6
WordPress WordPress>=5.2<5.2.7
WordPress WordPress>=5.3.0<5.3.4
WordPress WordPress>=5.4<5.4.2
Fedoraproject Fedora=31
Fedoraproject Fedora=32
Debian Debian Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/wordpress to a version that resolves this vulnerability.

    Fixed in 5.0.15+dfsg1-0+deb10u1Fixed in 5.0.19+dfsg1-0+deb10u1Fixed in 5.7.8+dfsg1-0+deb11u2Fixed in 6.1.1+dfsg1-1Fixed in 6.3.1+dfsg1-1
  2. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 5.4.2
  3. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 5.3.4
  4. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 5.2.7
  5. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 5.1.6
  6. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 5.0.10
  7. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.9.15
  8. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.8.14
  9. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.7.18
  10. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.6.19
  11. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.5.22
  12. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.4.23
  13. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.3.24
  14. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.2.28
  15. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.1.31
  16. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 4.0.31
  17. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 3.9.32
  18. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 3.8.34
  19. Upgrade

    Upgrade WordPress to a version that resolves this vulnerability.

    Fixed in 3.7.34

Event History

Jun 12, 2020
CVE Published
via MITRE·04:00 PM
Data Sourced
via MITRE·04:00 PM
DescriptionSeverityWeakness
Event
via MITRE·04:00 PM
Data Sourced
via OSV·04:15 PM
DescriptionSeverity

Frequently Asked Questions

1

What is the vulnerability ID for this WordPress vulnerability?

The vulnerability ID for this WordPress vulnerability is CVE-2020-4049.

2

What is the severity level of CVE-2020-4049?

CVE-2020-4049 has a severity level of low.

3

How can this vulnerability be exploited?

This vulnerability can be exploited by crafting the name of a theme folder in a way that could lead to JavaScript execution on the themes page in /wp-admin.

4

Who can exploit this vulnerability?

An admin with the ability to upload themes can exploit this vulnerability.

5

How can I fix CVE-2020-4049?

To fix CVE-2020-4049, update to WordPress version 5.4.2 or later.

Company

Resources

Contact

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