diff --git a/apps/extension/src/debug/__tests__/redact.test.ts b/apps/extension/src/debug/__tests__/redact.test.ts
index c2668661e..6a1c4d353 100644
--- a/apps/extension/src/debug/__tests__/redact.test.ts
+++ b/apps/extension/src/debug/__tests__/redact.test.ts
@@ -2,9 +2,41 @@
 
 import { describe, expect, it } from "vitest";
 import { jsonPointer, parseJsonSource } from "../json-source";
-import { BODY_CHARS, redactBody, redactRequestUrl } from "../redact";
+import { BODY_CHARS, redactBody, redactHeaders, redactRequestUrl } from "../redact";
 
 describe("source-preserving evidence redaction", () => {
+  it.each([
+    "PRIVATE-TOKEN",
+    "x-goog-api-key",
+    "x-amz-security-token",
+    "x-access-token",
+    "X-Vault-Token",
+    "Ocp-Apim-Subscription-Key",
+    "x-client-secret",
+  ])("redacts the vendor credential header %s", (name) => {
+    expect(redactHeaders({ [name]: "BSK_SYNTHETIC_SECRET_7264" })).toEqual({
+      [name.toLowerCase()]: "[redacted]",
+    });
+  });
+
+  it("redacts vendor credential fields in JSON bodies", () => {
+    const text =
+      '{"private_token":"BSK_SYNTHETIC_SECRET_7264","x_goog_api_key":"BSK_SYNTHETIC_SECRET_7264","page":2}';
+    expect(redactBody(text, "application/json")).toMatchObject({
+      text: '{"private_token":"[redacted]","x_goog_api_key":"[redacted]","page":2}',
+      redacted: true,
+    });
+  });
+
+  it.each([
+    "content-type",
+    "x-request-id",
+    "idempotency-key",
+    "x-tokenizer",
+  ])("keeps the ordinary header %s", (name) => {
+    expect(redactHeaders({ [name]: "value-7264" })).toEqual({ [name]: "value-7264" });
+  });
+
   it.each([
     'type="password"',
     'type="password"',
diff --git a/apps/extension/src/debug/redact.ts b/apps/extension/src/debug/redact.ts
index 98f0382b7..960d030e1 100644
--- a/apps/extension/src/debug/redact.ts
+++ b/apps/extension/src/debug/redact.ts
@@ -7,11 +7,25 @@ const MASK = "[redacted]";
 export const BODY_CHARS = 64 * 1024;
 export const URL_CHARS = 2048;
 
+/**
+ * Vendor credential names that name their secret in their last part: GitLab `private-token` (and the
+ * `private_token` query parameter), Google `x-goog-api-key`, AWS `x-amz-security-token`, Azure
+ * `ocp-apim-subscription-key`, Vault `x-vault-token`.
+ */
+const SECRET_HEADER_SUFFIX =
+  /(?:^|[_-])(?:token|api[_-]?key|apikey|secret|subscription[_-]key|password|passwd)$/i;
+
+function secretHeader(name: string): boolean {
+  return SECRET.test(name) || SECRET_HEADER_SUFFIX.test(name);
+}
+
 function secretField(key: string): boolean {
   return key
     .replace(/([a-z0-9])([A-Z])/g, "$1_$2")
     .split(/[.[\]]+/)
-    .some((part) => SECRET.test(part) || /(?:^|[_-])(?:password|passwd|pwd)(?:[_-]|$)/i.test(part));
+    .some(
+      (part) => secretHeader(part) || /(?:^|[_-])(?:password|passwd|pwd)(?:[_-]|$)/i.test(part),
+    );
 }
 
 const HTML_FIELD_SEPARATORS: Record<string, string> = {
@@ -97,7 +111,7 @@ export function redactHeaderEvidence(value: unknown): {
   let remaining = 4 * 1024;
   for (const [key, raw] of entries.slice(0, 80)) {
     const name = key.slice(0, 128).toLowerCase();
-    const secret = SECRET.test(name);
+    const secret = secretHeader(name);
     const original = String(raw);
     const redacted = secret ? MASK : redactText(original, 2048);
     const limit = Math.max(0, Math.min(2048, remaining - name.length));