# CVE-2020-1242: Microsoft Edge Information Disclosure Vulnerability

CVE-2020-1242 is fixed in 16 products on 1 platform, first by KB4561621, released June 9, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-1242
- Priority: Routine
- CVSS: 4.3 (Important)
- EPSS: 0.0386
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jun 9, 2020
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1242

## Description

<p>An information disclosure vulnerability exists in the way that Microsoft Edge handles cross-origin requests. An attacker who successfully exploited this vulnerability could determine the origin of all webpages in the affected browser.</p> <p>In a web-based attack scenario, an attacker could host a website that is used to attempt to exploit the vulnerability. Additionally, compromised websites and websites that accept or host user-provided content could contain specially crafted content that could be used to exploit the vulnerability. However, in all cases an attacker would have no way to force users to view attacker-controlled content. Instead, an attacker would have to convince users to take action. For example, an attacker could trick users into clicking a link that takes them to the attacker's site.</p> <p>The security update addresses the vulnerability by correcting how Microsoft Edge handles cross-origin requests.</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 | 17134.1550 | [KB4561621](https://patchblox.com/security/data/fix/microsoft/kb4561621.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for ARM64-based Systems | 17134.1550 | [KB4561621](https://patchblox.com/security/data/fix/microsoft/kb4561621.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1803 for x64-based Systems | 17134.1550 | [KB4561621](https://patchblox.com/security/data/fix/microsoft/kb4561621.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for 32-bit Systems | 17763.1282 | [KB4561608](https://patchblox.com/security/data/fix/microsoft/kb4561608.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for ARM64-based Systems | 17763.1282 | [KB4561608](https://patchblox.com/security/data/fix/microsoft/kb4561608.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1809 for x64-based Systems | 17763.1282 | [KB4561608](https://patchblox.com/security/data/fix/microsoft/kb4561608.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1903 for 32-bit Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1903 for ARM64-based Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1903 for x64-based Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1909 for 32-bit Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1909 for ARM64-based Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1909 for x64-based Systems |  | [KB4560960](https://patchblox.com/security/data/fix/microsoft/kb4560960.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 2004 for 32-bit Systems | 19041.329 | [KB4557957](https://patchblox.com/security/data/fix/microsoft/kb4557957.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 2004 for ARM64-based Systems | 19041.329 | [KB4557957](https://patchblox.com/security/data/fix/microsoft/kb4557957.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows 10 Version 2004 for x64-based Systems | 19041.329 | [KB4557957](https://patchblox.com/security/data/fix/microsoft/kb4557957.md) | Jun 9, 2020 |
| Microsoft | Microsoft Edge (EdgeHTML-based) on Windows Server 2019 | 17763.1282 | [KB4561608](https://patchblox.com/security/data/fix/microsoft/kb4561608.md) | Jun 9, 2020 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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