CVE-2025-27388
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedLoading arbitrary external URLs through WebView components introduces malicious JS code that can steal arbitrary user tokens.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceThis vulnerability allows loading arbitrary external URLs through WebView components, enabling malicious JavaScript code to execute within the WebView context and steal arbitrary user tokens. The issue stems from insufficient validation of URLs loaded in WebView components.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- Authentication
- X
- User interaction
- A
- Scope
- X
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify WebView usage in your applicationSearch your codebase for WebView implementations (e.g., android.webkit.WebView in Android, WKWebView in iOS, WebView2 in .NET, WebView in Electron). Review all files that instantiate or configure WebView components.Affected if Your application uses WebView components to render web content
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Check if external URL loading is permittedReview the WebView configuration code and look for methods like setLoadWithOverviewMode, setAllowContentAccess, setAllowFileAccess, or similar settings that control what URLs the WebView can load. Check for any allowlist or blocklist implementations.Affected if Your WebView is configured to load arbitrary external URLs without restriction
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Verify JavaScript execution is enabled for external contentExamine your WebView settings for JavaScript enablement (e.g., webSettings.setJavaScriptEnabled(true) in Android, javaScriptEnabled in configuration). Determine if this is applied to all loaded content or only to trusted sources.Affected if JavaScript execution is enabled and applied to external/untrusted URLs loaded in the WebView
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Inspect URL validation logicSearch the codebase for URL validation functions that filter or validate URLs before loading them into WebView. Look for patterns like whitelist validation, domain checks, or schema validation before loadUrl or loadRequest calls.Affected if No URL validation exists, or validation can be bypassed before passing URLs to WebView
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Check for Content Security Policy implementationReview HTML content loaded in WebView or HTTP headers for CSP meta tags or response headers (e.g., Content-Security-Policy header). Determine if CSP restricts script sources and token-accessible endpoints.Affected if No CSP headers are enforced, or CSP does not restrict external script sources and sensitive endpoint access
You are affected if your application uses WebView components that can load external URLs with JavaScript enabled without proper URL validation or Content Security Policy restrictions.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataRestrict WebView to load only trusted/internal URLs through allowlist validation, disable JavaScript execution for untrusted content, or implement Content Security Policy headers to prevent token theft.
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-27388 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-27388 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data