CVE-2019-20173

Login by Auth0 3.11.0 - 3.11.2 - Cross-Site Scripting

2020-01-31 00:00

Strategic Overview

Status: Patched in 3.11.3
Affected Plugin: Login by Auth0
Affected Version: 3.11.0 – 3.11.2
CVSS: 6.1Medium
Weakness type: CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE: CVE-2019-20173

At a glance

CVE-2019-20173 is a medium-severity Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in the Login by Auth0 WordPress plugin, affecting versions 3.11.0 – 3.11.2. It carries a CVSS score of 6.1 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 3.11.3; sites on affected versions should update now. Disclosed January 2020, reported by Muhamad Visat.

Vulnerability Overview

The Auth0 wp-auth0 plugin 3.11.x before 3.11.3 for WordPress allows XSS via a wle parameter associated with wp-login.php.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site.

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Reaching this weakness in Login by Auth0 3.11.0 – 3.11.2 takes a caller who can reach the endpoint. Cross-site scripting happens when input from a request is written into a page without being escaped for the context it lands in, so the browser parses attacker-supplied text as markup or script.

Injected script runs with the privileges of whoever views the affected page, which is how these flaws turn into administrator session theft, silent account creation or persistent backdoors in page content. For Login by Auth0 the fix is 3.11.3: builds 3.11.0 – 3.11.2 are affected, anything from 3.11.3 onward is not.

Remediation

Update to version 3.11.3, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Login by Auth0: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Login by Auth0 3.11.3 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2019-20173 https://www.wordfence.com/threat-intel/vulnerabilities/id/898c2851-27e9-493a-96c7-b6be1c1f5c7f https://nvd.nist.gov/vuln/detail/CVE-2019-20173

Related records

Same weakness class

Other vulnerabilities in Login by Auth0

CVSS Vector

6.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

This record contains material that is subject to copyright

CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE®). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy.

https://www.cve.org/Legal/TermsOfUse

Defiant hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute this software vulnerability information. Any copy of the software vulnerability information you make for such purposes is authorized provided that you include a hyperlink to this vulnerability record and reproduce Defiant's copyright designation and this license in any such copy.

https://www.wordfence.com/wordfence-intelligence-terms-and-conditions/