fix(core): Sanitize data URLs in http.client spans

Lms24 · Lms24 · commit 2a7a6a4451dd · 2026-01-20T11:30:50.000+01:00
diff --git a/packages/browser/src/integrations/globalhandlers.ts b/packages/browser/src/integrations/globalhandlers.ts
@@ -9,6 +9,7 @@ import {
   getLocationHref,
   isPrimitive,
   isString,
+  stripDataUrlContent,
   UNKNOWN_FUNCTION,
 } from '@sentry/core';
 import type { BrowserClient } from '../client';
@@ -208,14 +209,7 @@ function getFilenameFromUrl(url: string | undefined): string | undefined {
     return undefined;
   }
 
-  // stack frame urls can be data urls, for example when initializing a Worker with a base64 encoded script
-  // in this case we just show the data prefix and mime type to avoid too long raw data urls
-  if (url.startsWith('data:')) {
-    const match = url.match(/^data:([^;]+)/);
-    const mimeType = match ? match[1] : 'text/javascript';
-    const isBase64 = url.includes('base64,');
-    return `<data:${mimeType}${isBase64 ? ',base64' : ''}>`;
-  }
-
-  return url; // it's fine to not truncate it as it's not put in a regex (https://codeql.github.com/codeql-query-help/javascript/js-polynomial-redos)
+  // Strip data URL content to avoid long base64 strings in stack frames
+  // (e.g. when initializing a Worker with a base64 encoded script)
+  return stripDataUrlContent(url);
 }
diff --git a/packages/browser/src/tracing/request.ts b/packages/browser/src/tracing/request.ts
@@ -23,6 +23,7 @@ import {
   spanToJSON,
   startInactiveSpan,
   stringMatchesSomePattern,
+  stripDataUrlContent,
   stripUrlQueryAndFragment,
 } from '@sentry/core';
 import type { XhrHint } from '@sentry-internal/browser-utils';
@@ -199,7 +200,7 @@ export function instrumentOutgoingRequests(client: Client, _options?: Partial<Re
         const fullUrl = getFullURL(handlerData.fetchData.url);
         const host = fullUrl ? parseUrl(fullUrl).host : undefined;
         createdSpan.setAttributes({
-          'http.url': fullUrl,
+          'http.url': fullUrl ? stripDataUrlContent(fullUrl) : undefined,
           'server.address': host,
         });
 
@@ -355,7 +356,7 @@ function xhrCallback(
   const fullUrl = getFullURL(url);
   const parsedUrl = fullUrl ? parseUrl(fullUrl) : parseUrl(url);
 
-  const urlForSpanName = stripUrlQueryAndFragment(url);
+  const urlForSpanName = stripDataUrlContent(stripUrlQueryAndFragment(url));
 
   const hasParent = !!getActiveSpan();
 
@@ -364,10 +365,10 @@ function xhrCallback(
       ? startInactiveSpan({
           name: `${method} ${urlForSpanName}`,
           attributes: {
-            url,
+            url: stripDataUrlContent(url),
             type: 'xhr',
             'http.method': method,
-            'http.url': fullUrl,
+            'http.url': fullUrl ? stripDataUrlContent(fullUrl) : undefined,
             'server.address': parsedUrl?.host,
             [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.http.browser',
             [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'http.client',
diff --git a/packages/core/src/fetch.ts b/packages/core/src/fetch.ts
@@ -11,7 +11,12 @@ import { hasSpansEnabled } from './utils/hasSpansEnabled';
 import { isInstanceOf, isRequest } from './utils/is';
 import { getActiveSpan } from './utils/spanUtils';
 import { getTraceData } from './utils/traceData';
-import { getSanitizedUrlStringFromUrlObject, isURLObjectRelative, parseStringToURLObject } from './utils/url';
+import {
+  getSanitizedUrlStringFromUrlObject,
+  isURLObjectRelative,
+  parseStringToURLObject,
+  stripDataUrlContent,
+} from './utils/url';
 
 type PolymorphicRequestHeaders =
   | Record<string, string | undefined>
@@ -318,8 +323,9 @@ function getSpanStartOptions(
   spanOrigin: SpanOrigin,
 ): Parameters<typeof startInactiveSpan>[0] {
   const parsedUrl = parseStringToURLObject(url);
+  const sanitizedUrl = parsedUrl ? stripDataUrlContent(getSanitizedUrlStringFromUrlObject(parsedUrl)) : undefined;
   return {
-    name: parsedUrl ? `${method} ${getSanitizedUrlStringFromUrlObject(parsedUrl)}` : method,
+    name: sanitizedUrl ? `${method} ${sanitizedUrl}` : method,
     attributes: getFetchSpanAttributes(url, parsedUrl, method, spanOrigin),
   };
 }
@@ -331,15 +337,15 @@ function getFetchSpanAttributes(
   spanOrigin: SpanOrigin,
 ): SpanAttributes {
   const attributes: SpanAttributes = {
-    url,
+    url: stripDataUrlContent(url),
     type: 'fetch',
     'http.method': method,
     [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: spanOrigin,
     [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'http.client',
   };
   if (parsedUrl) {
     if (!isURLObjectRelative(parsedUrl)) {
-      attributes['http.url'] = parsedUrl.href;
+      attributes['http.url'] = stripDataUrlContent(parsedUrl.href);
       attributes['server.address'] = parsedUrl.host;
     }
     if (parsedUrl.search) {
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
@@ -313,6 +313,7 @@ export {
   getHttpSpanDetailsFromUrlObject,
   isURLObjectRelative,
   getSanitizedUrlStringFromUrlObject,
+  stripDataUrlContent,
 } from './utils/url';
 export {
   eventFromMessage,
diff --git a/packages/core/src/utils/url.ts b/packages/core/src/utils/url.ts
@@ -263,3 +263,26 @@ export function getSanitizedUrlString(url: PartialURL): string {
 
   return `${protocol ? `${protocol}://` : ''}${filteredHost}${path}`;
 }
+
+/**
+ * Strips the content from a data URL, returning a placeholder with the MIME type.
+ *
+ * Data URLs can be very long (e.g. base64 encoded scripts for Web Workers),
+ * with little valuable information, often leading to envelopes getting dropped due
+ * to size limit violations. Therefore, we strip data URLs and replace them with a
+ * placeholder.
+ *
+ * @param url - The URL to process
+ * @returns For data URLs, returns a short format like `<data:text/javascript,base64>`.
+ *          For non-data URLs, returns the original URL unchanged.
+ */
+export function stripDataUrlContent(url: string): string {
+  if (url.startsWith('data:')) {
+    // Match the MIME type (everything after 'data:' until the first ';' or ',')
+    const match = url.match(/^data:([^;,]+)/);
+    const mimeType = match ? match[1] : 'text/plain';
+    const isBase64 = url.includes(';base64,');
+    return `<data:${mimeType}${isBase64 ? ',base64' : ''}>`;
+  }
+  return url;
+}
diff --git a/packages/core/test/lib/utils/url.test.ts b/packages/core/test/lib/utils/url.test.ts
@@ -6,6 +6,7 @@ import {
   isURLObjectRelative,
   parseStringToURLObject,
   parseUrl,
+  stripDataUrlContent,
   stripUrlQueryAndFragment,
 } from '../../../src/utils/url';
 
@@ -638,3 +639,46 @@ describe('getHttpSpanDetailsFromUrlObject', () => {
     });
   });
 });
+
+describe('stripDataUrlContent', () => {
+  it('returns regular URLs unchanged', () => {
+    expect(stripDataUrlContent('https://example.com/api')).toBe('https://example.com/api');
+    expect(stripDataUrlContent('http://localhost:3000/test')).toBe('http://localhost:3000/test');
+    expect(stripDataUrlContent('/relative/path')).toBe('/relative/path');
+  });
+
+  it('strips content from base64 data URLs', () => {
+    expect(stripDataUrlContent('data:text/javascript;base64,SGVsbG8gV29ybGQ=')).toBe('<data:text/javascript,base64>');
+    expect(stripDataUrlContent('data:application/json;base64,eyJrZXkiOiJ2YWx1ZSJ9')).toBe(
+      '<data:application/json,base64>',
+    );
+    expect(stripDataUrlContent('data:text/html;base64,PGh0bWw+PC9odG1sPg==')).toBe('<data:text/html,base64>');
+  });
+
+  it('strips content from non-base64 data URLs', () => {
+    expect(stripDataUrlContent('data:text/plain,Hello%20World')).toBe('<data:text/plain>');
+    expect(stripDataUrlContent('data:text/html,<h1>Hello</h1>')).toBe('<data:text/html>');
+  });
+
+  it('handles data URLs with various MIME types', () => {
+    expect(stripDataUrlContent('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA')).toBe('<data:image/png,base64>');
+    expect(stripDataUrlContent('data:image/svg+xml;base64,PHN2Zz4=')).toBe('<data:image/svg+xml,base64>');
+    expect(stripDataUrlContent('data:application/octet-stream;base64,AQIDBA==')).toBe(
+      '<data:application/octet-stream,base64>',
+    );
+  });
+
+  it('defaults to text/plain for data URLs without MIME type', () => {
+    expect(stripDataUrlContent('data:,Hello')).toBe('<data:text/plain>');
+    expect(stripDataUrlContent('data:;base64,SGVsbG8=')).toBe('<data:text/plain,base64>');
+  });
+
+  it('handles empty data URLs', () => {
+    expect(stripDataUrlContent('data:')).toBe('<data:text/plain>');
+  });
+
+  it('handles very long base64 encoded data URLs', () => {
+    const longBase64 = 'A'.repeat(10000);
+    expect(stripDataUrlContent(`data:text/javascript;base64,${longBase64}`)).toBe('<data:text/javascript,base64>');
+  });
+});
diff --git a/packages/node/src/integrations/http.ts b/packages/node/src/integrations/http.ts
@@ -3,7 +3,13 @@ import { diag } from '@opentelemetry/api';
 import type { HttpInstrumentationConfig } from '@opentelemetry/instrumentation-http';
 import { HttpInstrumentation } from '@opentelemetry/instrumentation-http';
 import type { Span } from '@sentry/core';
-import { defineIntegration, getClient, hasSpansEnabled } from '@sentry/core';
+import {
+  defineIntegration,
+  getClient,
+  hasSpansEnabled,
+  SEMANTIC_ATTRIBUTE_URL_FULL,
+  stripDataUrlContent,
+} from '@sentry/core';
 import type { HTTPModuleRequestIncomingMessage, NodeClient, SentryHttpInstrumentationOptions } from '@sentry/node-core';
 import {
   addOriginToSpan,
@@ -282,6 +288,15 @@ function getConfigWithDefaults(options: Partial<HttpOptions> = {}): HttpInstrume
     requestHook: (span, req) => {
       addOriginToSpan(span, 'auto.http.otel.http');
 
+      // Sanitize data URLs to prevent long base64 strings in span attributes
+      const url = getRequestUrl(req as ClientRequest);
+      if (url.startsWith('data:')) {
+        const sanitizedUrl = stripDataUrlContent(url);
+        span.setAttribute('http.url', sanitizedUrl);
+        span.setAttribute(SEMANTIC_ATTRIBUTE_URL_FULL, sanitizedUrl);
+        span.updateName(`${(req as ClientRequest).method || 'GET'} ${sanitizedUrl}`);
+      }
+
       options.instrumentation?.requestHook?.(span, req);
     },
     responseHook: (span, res) => {
diff --git a/packages/node/src/integrations/node-fetch.ts b/packages/node/src/integrations/node-fetch.ts
@@ -1,7 +1,15 @@
 import type { UndiciInstrumentationConfig } from '@opentelemetry/instrumentation-undici';
 import { UndiciInstrumentation } from '@opentelemetry/instrumentation-undici';
 import type { IntegrationFn } from '@sentry/core';
-import { defineIntegration, getClient, hasSpansEnabled, SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN } from '@sentry/core';
+import {
+  defineIntegration,
+  getClient,
+  hasSpansEnabled,
+  SEMANTIC_ATTRIBUTE_SENTRY_CUSTOM_SPAN_NAME,
+  SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
+  SEMANTIC_ATTRIBUTE_URL_FULL,
+  stripDataUrlContent,
+} from '@sentry/core';
 import type { NodeClient } from '@sentry/node-core';
 import { generateInstrumentOnce, SentryNodeFetchInstrumentation } from '@sentry/node-core';
 import type { NodeClientOptions } from '../types';
@@ -101,7 +109,20 @@ function getConfigWithDefaults(options: Partial<NodeFetchOptions> = {}): UndiciI
 
       return !!shouldIgnore;
     },
-    startSpanHook: () => {
+    startSpanHook: request => {
+      const url = getAbsoluteUrl(request.origin, request.path);
+
+      // Sanitize data URLs to prevent long base64 strings in span attributes
+      if (url.startsWith('data:')) {
+        const sanitizedUrl = stripDataUrlContent(url);
+        return {
+          [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.http.otel.node_fetch',
+          'http.url': sanitizedUrl,
+          [SEMANTIC_ATTRIBUTE_URL_FULL]: sanitizedUrl,
+          [SEMANTIC_ATTRIBUTE_SENTRY_CUSTOM_SPAN_NAME]: `${request.method || 'GET'} ${sanitizedUrl}`,
+        };
+      }
+
       return {
         [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.http.otel.node_fetch',
       };
