CVE-2017-16562

published 2017-11-10

CVE-2017-16562: The UserPro plugin before 4.9.17.1 for WordPress, when used on a site with the "admin" username, allows remote attackers to bypass authentication and obtain…

Priority P1 85 critical 9.8 CVSS 3.0

AV N AC L PR N UI N S U C H I H A H

ITW EXPLOIT VulnCheck KEV

The UserPro plugin before 4.9.17.1 for WordPress, when used on a site with the "admin" username, allows remote attackers to bypass authentication and obtain administrative access via a "true" value for the up_auto_log parameter in the QUERY_STRING to the default URI.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
userproplugin	userpro	< 4.9.17.1	4.9.17.1

Detection & IOCs extracted from sources · hover to see the quote

url http://www.targetsite.com/?up_auto_log=true↗

other up_auto_log=true↗

• → Detect HTTP requests containing the query string parameter 'up_auto_log=true' targeting WordPress sites with the UserPro plugin installed. ↗
• → The attack only succeeds on WordPress sites where the default 'admin' username exists; monitor for unexpected admin session creation following requests with this query string. ↗
• → Use Google Dork 'inurl:/plugins/userpro' to identify potentially vulnerable targets exposed publicly. ↗

• · The authentication bypass is only exploitable when the WordPress site has a user with the exact username 'admin'; sites using non-default admin usernames are not affected. ↗
• · Vulnerable versions are UserPro plugin <= 4.9.17.1 (specifically tested on <= 4.6.17 with WordPress 4.8.3); versions 4.9.17.1 and above contain the vendor fix. ↗

CVSS provenance

nvd v3.0 9.8 CRITICAL CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 7.5 HIGH AV:N/AC:L/Au:N/C:P/I:P/A:P

vulncheck 9.8 CRITICAL

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