CVE-2020-16873
Xamarin.Forms Spoofing Vulnerability
<p>A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on Android WebView version prior to 83.0.4103.106. This vulnerability could allow an attacker to execute arbitrary Javascript code on a target system.</p> <p>For the attack to be successful, the targeted user would need to browse to a malicious website or a website serving the malicious code through Xamarin.Forms.</p> <p>The security update addresses this vulnerability by preventing the malicious Javascript from running in the WebView.</p>
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Xamarin.Forms Spoofing Vulnerability
<p>A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on Android WebView version prior to 83.0.4103.106. This vulnerability could allow an attacker to execute arbitrary Javascript code on a target system.</p> <p>For the attack to be successful, the targeted user would need to browse to a malicious website or a website serving the malicious code through Xamarin.Forms.</p> <p>The security update addresses this vulnerability by preventing the malicious Javascript from running in the WebView.</p>
- Record
CVE-2020-16873- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N/E:F/RL:O/RC:C/CR:M/MAV:N/MAC:L/MPR:N/MUI:R/MS:C - Updated
- 2026-11-02
EUVDEUVD-2020-8831
<p>A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on Android WebView version prior to 83.0.4103.106. This vulnerability could allow an attacker to execute arbitrary Javascript code on a target system.</p> <p>For the attack to be successful, the targeted user would need to browse to a malicious website or a website serving the malicious code through Xamarin.Forms.</p> <p>The security update addresses this vulnerability by preventing the malicious Javascript from running in the WebView.</p>
- Record
EUVD-2020-8831- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N/E:F/RL:O/RC:C/CR:M/MAV:N/MAC:L/MPR:N/MUI:R/MS:C - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mc93-wcph-m2mx
A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on...
A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on Android WebView version prior to 83.0.4103.106, aka 'Xamarin.Forms Spoofing Vulnerability'.
- Record
GHSA-mc93-wcph-m2mx- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N - Weakness
- CWE-1188
- Updated
- 2026-11-02
NVD
<p>A spoofing vulnerability manifests in Microsoft Xamarin.Forms due to the default settings on Android WebView version prior to 83.0.4103.106. This vulnerability could allow an attacker to execute arbitrary Javascript code on a target system.</p> <p>For the attack to be successful, the targeted user would need to browse to a malicious website or a website serving the malicious code through Xamarin.Forms.</p> <p>The security update addresses this vulnerability by preventing the malicious Javascript from running in the WebView.</p>
- Record
CVE-2020-16873- CVSS 3.1
- 4.7 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-1188
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-16873 is a medium vulnerability (CVSS 4.7) in Microsoft Xamarin.forms, published September 11, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 3.97%, the 90th percentile. No source names a fixed version.