# CVE-2018-8383: Microsoft Edge Spoofing Vulnerability

CVE-2018-8383 is fixed in 2 products on 1 platform, first by KB4343909, released August 14, 2018. It is not reported as exploited, but the vendor rates exploitation more likely. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2018-8383
- Priority: Urgent
- CVSS: 4.3 (Important)
- EPSS: 0.0761
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation More Likely
- Published: Aug 14, 2018
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2018-8383

## Description

<p>A spoofing vulnerability exists when Microsoft Edge does not properly parse HTTP content. An attacker who successfully exploited this vulnerability could trick a user by redirecting the user to a specially crafted website. The specially crafted website could either spoof content or serve as a pivot to chain an attack with other vulnerabilities in web services.</p> <p>To exploit the vulnerability, the user must click a specially crafted URL. In an email attack scenario, an attacker could send an email message containing the specially crafted URL to the user in an attempt to convince the user to click it.</p> <p>In a web-based attack scenario, an attacker could host a specially crafted website designed to appear as a legitimate website to the user. However, the attacker would have no way to force the user to visit the specially crafted website. The attacker would have to convince the user to visit the specially crafted website, typically by way of enticement in an email or instant message, and then convince the user to interact with content on the website.</p> <p>The update addresses the vulnerability by correcting how Microsoft Edge parses HTTP responses.</p>

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for 32-bit Systems | 17134.228 | [KB4343909](https://patchblox.com/security/data/fix/microsoft/kb4343909.md) | Aug 14, 2018 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for x64-based Systems | 17134.228 | [KB4343909](https://patchblox.com/security/data/fix/microsoft/kb4343909.md) | Aug 14, 2018 |

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