What’s Vulnerable › Vulnerabilities

CVE-2018-20149

• Severity: medium (CVSS 5.4 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-12-14 · updated 2026-06-17
• Weakness: CWE-79

Description

In WordPress before 4.9.9 and 5.x before 5.0.1, when the Apache HTTP Server is used, authors could upload crafted files that bypass intended MIME type restrictions, leading to XSS, as demonstrated by a .jpg file without JPEG data.

Affected products

• Debian Linux: 8.0, 9.0
• WordPress: before 4.9.9; from 5.0 before 5.0.1 — fixed in 4.9.9, 5.0.1

How to fix

Upgrade to a fixed version: WordPress 4.9.9, 5.0.1. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/106220
• https://codex.wordpress.org/Version_4.9.9
• https://github.com/WordPress/WordPress/commit/246a70bdbfac3bd45ff71c7941deef1bb206b19a
• https://lists.debian.org/debian-lts-announce/2019/02/msg00019.html
• https://wordpress.org/news/2018/12/wordpress-5-0-1-security-release/
• https://wordpress.org/support/wordpress-version/version-5-0-1/
• https://wpvulndb.com/vulnerabilities/9175
• https://www.debian.org/security/2019/dsa-4401
• https://www.zdnet.com/article/wordpress-plugs-bug-that-led-to-google-indexing-some-user-passwords/
• http://www.securityfocus.com/bid/106220
• https://codex.wordpress.org/Version_4.9.9
• https://github.com/WordPress/WordPress/commit/246a70bdbfac3bd45ff71c7941deef1bb206b19a

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