Express
CVE-2014-6393
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V1 - Encoding and Sanitization Output encoding, context-aware escaping
MITRE ATT&CK
2 techniques across 2 tactics: Initial Access, Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 6.1 (MEDIUM). Attack characteristics: network attack vector, low complexity, no privileges required, user interaction required. EPSS exploitation probability: 0.29%. |
| Exploit ScenarioDerived | A remote attacker could inject malicious scripts into web pages viewed by other users by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
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. Rated medium severity (CVSS 6.1), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This Cross-Site Scripting (XSS) vulnerability could allow attackers to inject malicious scripts into web pages viewed by other users.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Sanitize all user input, use Content-Security-Policy headers, encode output contextually (HTML, JS, URL). Use frameworks with built-in XSS protection.
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in npm
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Cross-Site Scripting (XSS) (CWE-79), which allows attackers to inject malicious scripts into web pages viewed by other users. 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. Affected products include: Openjsf Express. Version information: before 3.11.
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Severity by source
AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionCVE.org
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.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Cross-Site Scripting occurs when an application accepts untrusted data and sends it to a web browser without proper validation or encoding.
Affected Products (CPE)CVE.org
qs before 6.10.3, as used in Express before 4.17.3 and other products, allows attackers to cause a Node process hang for
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Authenticated command injection in Ubiquiti UniFi OS allows low-privileged network-adjacent attackers to execute arbitra
Privilege escalation in Ubiquiti UniFi OS allows a low-privileged attacker with network access to elevate privileges on
A vulnerability has been identified in the Express response.links function, allowing for arbitrary resource injection in
Authentication bypass in Ubiquiti UniFi OS lets a network-adjacent attacker circumvent login on affected devices by inje
Denial of Service vulnerability in Multer (Node.js multipart form-data middleware) affecting versions 1.4.4-lts.1 throug
Information disclosure in Ubiquiti UniFi OS devices allows unauthenticated network-adjacent attackers to read sensitive
Unauthenticated network attackers can crash Ubiquiti UniFi gateway devices by sending crafted traffic that triggers an o
Denial of service in Ubiquiti UniFi gateway devices (Dream Machines, Dream Routers, Dream Wall, Cloud Gateways, Enterpri
Unauthenticated network attackers who can reach an affected Ubiquiti UniFi gateway can trigger an out-of-bounds read (CW
Denial of service in UniFi gateway devices (Dream Machines, Dream Routers, Dream Wall, Cloud Gateways, Enterprise Firewa
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB