ZyXEL ATP500/USG40/USG1900/ZyWALL310/ZyWALL1100 /?mobile=1 mp_idx Reflected cross site scripting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in ZyXEL ATP500, USG40, USG1900, ZyWALL310 and ZyWALL1100 (Firewall Software). It has been declared as problematic. Affected by this vulnerability is an unknown part of the file /?mobile=1. The manipulation of the argument mp_idx with the input value %22;alert(1);// leads to a cross site scripting vulnerability (Reflected). The CWE definition for the vulnerability is CWE-79. As an impact it is known to affect integrity. An attacker might be able to inject arbitrary html and script code into the web site. This would alter the appearance and would make it possible to initiate further attacks against site visitors.

The bug was discovered 02/06/2019. The weakness was presented 04/15/2019 by Aaron Bishop as CVE-2019-9955 Refelected XSS on Zyxel Login page as confirmed advisory (Website). It is possible to read the advisory at securitymetrics.com. The public release was coordinated in cooperation with ZyXEL. This vulnerability is known as CVE-2019-9955 since 03/23/2019. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details and also a public exploit are known. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

A public exploit has been developed by Aaron Bishop in URL/Javascript and been published immediately after the advisory. It is declared as proof-of-concept. It is possible to download the exploit at securitymetrics.com. The vulnerability was handled as a non-public zero-day exploit for at least 18 days. During that time the estimated underground price was around $0-$5k.

Applying a patch is able to eliminate this problem. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

Additional details are provided at seclists.org.





CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 4.7

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍



VulDB Base Score: 🔍
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Name: Reflected
Class: Cross site scripting / Reflected
ATT&CK: T1059.007

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: Aaron Bishop
Programming Language: 🔍
Download: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfoedit

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Adversaries: 🔍
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Recommended: Patch
Status: 🔍

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Patch: securitymetrics.com


02/06/2019 🔍
02/06/2019 +0 days 🔍
02/24/2019 +18 days 🔍
02/24/2019 +0 days 🔍
03/23/2019 +27 days 🔍
04/15/2019 +23 days 🔍
04/15/2019 +0 days 🔍
04/16/2019 +1 days 🔍
05/30/2020 +410 days 🔍


Vendor: https://www.zyxel.com/

Advisory: CVE-2019-9955 Refelected XSS on Zyxel Login page
Researcher: Aaron Bishop
Status: Confirmed
Confirmation: 🔍
Coordinated: 🔍

CVE: CVE-2019-9955 (🔍)
scip Labs: https://www.scip.ch/en/?labs.20161013
Misc.: 🔍


Created: 04/16/2019 08:22 PM
Updated: 05/30/2020 06:39 AM
Changes: (2) advisory_confirm_url source_cve_assigned
Complete: 🔍


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