Android WebView Universal Cross-site Scripting

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

EPSS

• CVE-2020-6506: 3.72% estimated exploitation activity in the next 30 days; percentile 89.80 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

A universal cross-site scripting (UXSS) vulnerability, CVE-2020-6506 (https://crbug.com/1083819), has been identified in the Android WebView system component, which allows cross-origin iframes to execute arbitrary JavaScript in the top-level document. This vulnerability affects React Native apps which use a react-native-webview that allows navigation to arbitrary URLs, and when that app runs on systems with an Android WebView version prior to 83.0.4103.106. Pending mitigation Ensure users update their Android WebView system component via the Google Play Store to 83.0.4103.106 or higher to avoid this UXSS. 'react-native-webview' is working on a mitigation but it could take some time. References https://alesandroortiz.com/articles/uxss-android-webview-cve-2020-6506/

Published by the source

2 Oct 2020, 16:22 UTC

Last modified by the source

8 Nov 2023, 04:03 UTC

Source last checked

26 Oct 2026, 12:16 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-36j3-xxf7-4pqg

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-36j3-xxf7-4pqg

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2020-6506

Advisory: Android WebView Universal Cross-site Scripting
IDs: CVE-2020-6506, GHSA-36j3-xxf7-4pqg
Record: https://patchnext.com/advisories/cve-2020-6506 (revision 2, source checked 26 Oct 2026, 12:16 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: react-native-webview 11.0.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm react-native-webview: affected <= 10.10.2; fixed in 11.0.0

## Suggested inspection (read-only)
- `npm ls react-native-webview --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on react-native-webview.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-36j3-xxf7-4pqg (OSV record GHSA-36j3-xxf7-4pqg lists affected ranges: npm react-native-webview >=0 <11.0.0 (fixed))
- Verified: https://github.com/advisories/GHSA-36j3-xxf7-4pqg (GitHub-reviewed advisory GHSA-36j3-xxf7-4pqg lists affected ranges: npm react-native-webview >=0 <=10.10.2)

Commands are suggestions: review each one before running it.