Express Web Framework up to 3.10/4.4 on Node.js 400 Level Response charset 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 Express Web Framework up to 3.10/4.4 on Node.js (JavaScript Library). It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component 400 Level Response Handler. The manipulation of the argument charset as part of a Content-Type Header leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

The Express web framework before 3.11 and 4.x before 4.5 for Node.js does not provide a charset field in HTTP Content-Type headers in 400 level responses, which might allow remote attackers to conduct cross-site scripting (XSS) attacks via characters in a non-standard encoding.

The bug was discovered 03/18/2015. The weakness was disclosed 08/09/2017 as Bug 1203190 as not defined bug report (Bugzilla). It is possible to read the advisory at This vulnerability is known as CVE-2014-6393 since 09/15/2014. 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 of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 875 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 3.11 or 4.5 eliminates this vulnerability.




CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Cross site scripting
CWE: CWE-79 / CWE-74 / CWE-707
ATT&CK: T1059.007

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Express Web Framework 3.11/4.5


09/15/2014 🔍
03/18/2015 +184 days 🔍
08/09/2017 +875 days 🔍
08/09/2017 +0 days 🔍
08/10/2017 +1 days 🔍
11/05/2019 +817 days 🔍


Advisory: Bug 1203190
Status: Not defined
Confirmation: 🔍

CVE: CVE-2014-6393 (🔍)


Created: 08/10/2017 08:23 AM
Updated: 11/05/2019 04:10 PM
Changes: 08/10/2017 08:23 AM (63), 11/05/2019 04:10 PM (2)
Complete: 🔍


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