CVE-2009-1030

Cross-site scripting (XSS) vulnerability in the choose_primary_blog function in wp-includes/wpmu...

4.3 MediumPublic exploit

Cross-site scripting (XSS) vulnerability in the choose_primary_blog function in wp-includes/wpmu-functions.php in WordPress MU (WPMU) before 2.7 allows remote attackers to inject arbitrary web script or HTML via the HTTP Host header.

Exploit likelihood

4.66%Up 1.7 points since Feb 4, 2022

What each source reports

NVD Score used 4.3

Record: CVE-2009-1030
CVSS 2.0: 4.3 MediumAV:N/AC:M/Au:N/C:N/I:P/A:N
Weakness: CWE-79
Updated: 2026-11-02

CVE List No score

Record: CVE-2009-1030
Updated: 2026-11-02

EUVDEUVD-2009-1031 No score

Record: EUVD-2009-1031
Updated: 2026-11-03

GitHub AdvisoriesGHSA-fg2g-28hw-pqvr No score

Cross-site scripting (XSS) vulnerability in the choose_primary_blog function in wp-includes/wpmu...

Record: GHSA-fg2g-28hw-pqvr
Weakness: CWE-79
Updated: 2026-11-02

Affected products

wordpress mu

Public exploits

Links only. Every CVE stores no exploit code.

Public exploits
Source	Link	Date
Exploit-DB	WordPress MU < 2.7 - 'HOST' HTTP Header Cross-Site Scripting	2009-03-10

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, Exploit-DB, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2009-1030 is a medium vulnerability (CVSS 4.3) in Wordpress Mu, published March 20, 2009. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 4.66%, the 91st percentile. No source names a fixed version.