diff --git a/.jules/sentinel.md b/.jules/sentinel.md
index e644cad..bdb431f 100644
--- a/.jules/sentinel.md
+++ b/.jules/sentinel.md
@@ -39,3 +39,8 @@
 **Vulnerability:** The `filterSensitiveFields` function in `src/providers/index.ts` used a manual recursive loop to drop sensitive keys, but it failed to recurse into arrays. If a configuration object contained an array with sensitive nested objects, those secrets would be leaked in debug logs.
 **Learning:** Manual object traversal for redaction is prone to edge cases (like arrays or circular references).
 **Prevention:** Use a custom replacer function with `JSON.stringify` to safely and completely redact sensitive fields across all nested structures.
+
+## 2026-06-29 - Insufficient Broad Pattern Matching for Secrets
+**Vulnerability:** The `SENSITIVE_KEY_PATTERNS` array used for redacting sensitive fields did not include patterns for `bearer`, `session`, `jwt`, and `cookie`. Any of these authentication tokens passed within headers or configuration would be logged in plaintext in error logs and debug outputs.
+**Learning:** Hardcoded allowlists or blocklists for secrets need to be comprehensive and cover a wide variety of standard authentication schemes.
+**Prevention:** Regularly audit redaction pattern lists against modern authentication methods (like JWTs, bearer tokens, and session cookies).
diff --git a/src/sensitive.ts b/src/sensitive.ts
index 3917a58..6bf387e 100644
--- a/src/sensitive.ts
+++ b/src/sensitive.ts
@@ -8,6 +8,10 @@ const SENSITIVE_KEY_PATTERNS = [
   "auth",
   "credential",
   "authorization",
+  "bearer",
+  "session",
+  "jwt",
+  "cookie",
 ];
 
 export function isSensitiveKey(key: string): boolean {
diff --git a/tests/security.test.ts b/tests/security.test.ts
index b8e9808..70ba9c3 100644
--- a/tests/security.test.ts
+++ b/tests/security.test.ts
@@ -134,6 +134,10 @@ describe("security", () => {
       expect(isSensitiveKey("x-api-token")).toBe(true);
       expect(isSensitiveKey("clientSecret")).toBe(true);
       expect(isSensitiveKey("credentialRef")).toBe(true);
+      expect(isSensitiveKey("bearerToken")).toBe(true);
+      expect(isSensitiveKey("session_id")).toBe(true);
+      expect(isSensitiveKey("jwt_payload")).toBe(true);
+      expect(isSensitiveKey("cookie")).toBe(true);
       expect(isSensitiveKey("Content-Type")).toBe(false);
     });
 
@@ -171,6 +175,10 @@ describe("security", () => {
         access_token: "should-be-filtered",
         apiKey: "should-be-filtered",
         clientSecret: "should-be-filtered",
+        bearer_token: "should-be-filtered",
+        session_id: "should-be-filtered",
+        jwt_token: "should-be-filtered",
+        cookie: "should-be-filtered",
         normal_field: "should-remain",
         base_url: "should-remain",
       };
@@ -187,6 +195,10 @@ describe("security", () => {
       expect(filtered).not.toHaveProperty("access_token");
       expect(filtered).not.toHaveProperty("apiKey");
       expect(filtered).not.toHaveProperty("clientSecret");
+      expect(filtered).not.toHaveProperty("bearer_token");
+      expect(filtered).not.toHaveProperty("session_id");
+      expect(filtered).not.toHaveProperty("jwt_token");
+      expect(filtered).not.toHaveProperty("cookie");
     });
 
     it("should be case-insensitive", () => {