Tauri: Origin Confusion Allows Remote Pages to Invoke Local-Only IPC Commands

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Tauri is a framework for building binaries for all major desktop platforms. From 2.0 to 2.11.0, a flaw in Tauri's is_local_url() function causes it to incorrectly classify remote URLs as trusted local origins on Windows and Android. On these systems, Tauri maps custom URI scheme protocols to http://<scheme>.localhost/ because those platforms' WebView implementations cannot serve custom URI schemes directly. The issue is that Tauri's check to see if the origin is local, only checks the first subdomain of the URL. An attacker can abuse this by hosting a page on a domain whose subdomain matches the custom scheme of the application. This vulnerability is fixed in 2.10.3.

Source published

27 May 2026 14:29:53 UTC

Source modified

27 May 2026 15:40:09 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · 6.1 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N

Tauri is a framework for building binaries for all major desktop platforms. From 2.0 to 2.11.0, a flaw in Tauri's is_local_url() function causes it to incorrectly classify remote URLs as trusted local origins on Windows and Android. On these systems, Tauri maps custom URI scheme protocols to http://<scheme>.localhost/ because those platforms' WebView implementations cannot serve custom URI schemes directly. The issue is that Tauri's check to see if the origin is local, only checks the first subdomain of the URL. An attacker can abuse this by hosting a page on a domain whose subdomain matches the custom scheme of the application. This vulnerability is fixed in 2.10.3.

Source published

May 27, 2026, 2:29:53 PM (timezone not stated)

Source modified

May 27, 2026, 3:40:09 PM (timezone not stated)

Observed here

7 Nov 2026 09:32:19 UTC

Source terms

ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 4.0 · 6.1 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N

Tauri is a framework for building binaries for all major desktop platforms. From 2.0 to 2.11.0, a flaw in Tauri's is_local_url() function causes it to incorrectly classify remote URLs as trusted local origins on Windows and Android. On these systems, Tauri maps custom URI scheme protocols to http://<scheme>.localhost/ because those platforms' WebView implementations cannot serve custom URI schemes directly. The issue is that Tauri's check to see if the origin is local, only checks the first subdomain of the URL. An attacker can abuse this by hosting a page on a domain whose subdomain matches the custom scheme of the application. This vulnerability is fixed in 2.10.3.

Source published

27 May 2026 15:16:27 UTC

Source modified

26 Oct 2026 11:10:00 UTC

Observed here

27 Oct 2026 11:12:01 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 4.0 · [email protected] · Secondary · 6.1 CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/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

CVSS 3.1 · [email protected] · Primary · 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

### Summary A flaw in Tauri's `is_local_url()` function causes it to incorrectly classify remote URLs as trusted local origins on Windows and Android. On these systems, Tauri maps custom URI scheme protocols to `http://<scheme>.localhost/` because those platforms' WebView implementations cannot serve custom URI schemes directly. The issue is that Tauri's check to see if the origin is local, only checks the first subdomain of the URL. An attacker can abuse this by hosting a page on a domain whose subdomain matches the custom scheme of the application (e.g. http://app.attacker.com/)." Example: - Local URL: `app://localhost/` → on Android/Windows: `http://app.localhost/` - The check passes for any URL starting with `http://app.`, including `http://app.evil.com/` As a result, the attacker page can invoke backend commands that the developer intended to be accessible only to the app's own frontend and that are explicitly restricted from being called by external or remote origins. ### Details Vulnerable function: ```rust #[cfg(any(windows, target_os = "android"))] let local = { let protocol_url = self.manager().tauri_protocol_url(uses_https); let maybe_protocol = current_url .domain() .and_then(|d| d.split_once('.')) // BUG: only splits on first dot .unwrap_or_default() .0; protocols.contains_key(maybe_protocol) && scheme == protocol_url.scheme() }; ``` Link: https://github.com/tauri-apps/tauri/blob/1ef6a119b1571d1da0acc08bdb7fd5521a4c6d52/crates/tauri/src/webview/mod.rs#L1680 `split_once('.')` discards everything after the first `.`. For http://app.evil.com/, the extracted label is app. If the application has registered a protocol named app, `protocols.contains_key("app")` returns `true` and the URL is classified as `Origin::Local`. The correct check must assert the full domain is exactly `<protocol>.localhost`. ### PoC We created a proof of concept app that can be found [here](https://drive.google.com/file/d/1YME6YMSKv69JxFF7Ne0OrZ6tGC_OH7Jw/view?usp=sharing). The app registers a custom app:// protocol and exposes a ping command restricted to local origins only. It provides a button to open a URL in a WebView, pre-filled with https://app.robbe-bc9.workers.dev/, an attacker-controlled page that invokes ping on load. Because the domain's first label matches the registered app protocol, is_local_url() classifies it as a local origin and the command succeeds. `capabilities/main.json` contains the following code, which only exposes `ping` locally: ```json { "$schema": "../../../crates/tauri-schema-generator/schemas/capability.schema.json", "identifier": "main", "local": true, "windows": ["*"], "permissions": [ "sample:allow-ping" ] } ``` `src/lib.rs` contains the following code, to register a custom scheme: ```rust tauri::Builder::default() .register_uri_scheme_protocol("app", |_ctx, _request| { ... }) ``` ### Impact The attacker page can invoke backend commands that the developer intended to be accessible only to the app's own frontend and that are explicitly restricted from being called by external or remote origins.

Source published

6 May 2026 16:58:35 UTC

Source modified

8 Jun 2026 23:45:13 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS_V4 · CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N

Publisher rating · MODERATE