diff --git a/src/components/oauth/ConsentPage.tsx b/src/components/oauth/ConsentPage.tsx
index 817be11..f41a7e8 100644
--- a/src/components/oauth/ConsentPage.tsx
+++ b/src/components/oauth/ConsentPage.tsx
@@ -11,6 +11,7 @@ import { authClient } from '@/lib/auth-client';
 import { apiRequest, showErrorToast } from '@/lib/utils';
 import { toast, Toaster } from 'sonner';
 import { Shield, User, Mail, ChevronRight, AlertTriangle, Loader2 } from 'lucide-react';
+import { isValidRedirectUri, parseRedirectUris } from '@/lib/utils/oauth-validation';
 
 interface OAuthApplication {
   id: string;
@@ -44,6 +45,7 @@ export default function ConsentPage() {
       const params = new URLSearchParams(window.location.search);
       const clientId = params.get('client_id');
       const scope = params.get('scope');
+      const redirectUri = params.get('redirect_uri');
 
       if (!clientId) {
         setError('Invalid authorization request: missing client ID');
@@ -59,6 +61,16 @@ export default function ConsentPage() {
         return;
       }
 
+      // Validate redirect URI if provided
+      if (redirectUri) {
+        const authorizedUris = parseRedirectUris(app.redirectURLs);
+        
+        if (!isValidRedirectUri(redirectUri, authorizedUris)) {
+          setError('Invalid authorization request: unauthorized redirect URI');
+          return;
+        }
+      }
+
       setApplication(app);
 
       // Parse requested scopes
@@ -91,8 +103,27 @@ export default function ConsentPage() {
         // If denied, redirect back to the application with error
         const params = new URLSearchParams(window.location.search);
         const redirectUri = params.get('redirect_uri');
-        if (redirectUri) {
-          window.location.href = `${redirectUri}?error=access_denied`;
+        
+        if (redirectUri && application) {
+          // Validate redirect URI against authorized URIs
+          const authorizedUris = parseRedirectUris(application.redirectURLs);
+          
+          if (isValidRedirectUri(redirectUri, authorizedUris)) {
+            try {
+              // Parse and reconstruct the URL to ensure it's safe
+              const url = new URL(redirectUri);
+              url.searchParams.set('error', 'access_denied');
+              
+              // Safe to redirect - URI has been validated and sanitized
+              window.location.href = url.toString();
+            } catch (e) {
+              console.error('Failed to parse redirect URI:', e);
+              setError('Invalid redirect URI');
+            }
+          } else {
+            console.error('Unauthorized redirect URI:', redirectUri);
+            setError('Invalid redirect URI');
+          }
         }
       }
     } catch (error) {
diff --git a/src/lib/utils/oauth-validation.test.ts b/src/lib/utils/oauth-validation.test.ts
new file mode 100644
index 0000000..1580ef7
--- /dev/null
+++ b/src/lib/utils/oauth-validation.test.ts
@@ -0,0 +1,85 @@
+import { describe, test, expect } from "bun:test";
+import { isValidRedirectUri, parseRedirectUris } from "./oauth-validation";
+
+describe("OAuth Validation", () => {
+  describe("parseRedirectUris", () => {
+    test("parses comma-separated URIs", () => {
+      const result = parseRedirectUris("https://app1.com,https://app2.com, https://app3.com ");
+      expect(result).toEqual([
+        "https://app1.com",
+        "https://app2.com",
+        "https://app3.com"
+      ]);
+    });
+
+    test("handles empty string", () => {
+      expect(parseRedirectUris("")).toEqual([]);
+    });
+
+    test("filters out empty values", () => {
+      const result = parseRedirectUris("https://app1.com,,https://app2.com,");
+      expect(result).toEqual(["https://app1.com", "https://app2.com"]);
+    });
+  });
+
+  describe("isValidRedirectUri", () => {
+    test("validates exact match", () => {
+      const authorizedUris = ["https://app.example.com/callback"];
+      
+      expect(isValidRedirectUri("https://app.example.com/callback", authorizedUris)).toBe(true);
+      expect(isValidRedirectUri("https://app.example.com/other", authorizedUris)).toBe(false);
+    });
+
+    test("validates wildcard paths", () => {
+      const authorizedUris = ["https://app.example.com/*"];
+      
+      expect(isValidRedirectUri("https://app.example.com/", authorizedUris)).toBe(true);
+      expect(isValidRedirectUri("https://app.example.com/callback", authorizedUris)).toBe(true);
+      expect(isValidRedirectUri("https://app.example.com/deep/path", authorizedUris)).toBe(true);
+      
+      // Different domain should fail
+      expect(isValidRedirectUri("https://evil.com/callback", authorizedUris)).toBe(false);
+    });
+
+    test("validates protocol", () => {
+      const authorizedUris = ["https://app.example.com/callback"];
+      
+      // HTTP instead of HTTPS should fail
+      expect(isValidRedirectUri("http://app.example.com/callback", authorizedUris)).toBe(false);
+    });
+
+    test("validates host and port", () => {
+      const authorizedUris = ["https://app.example.com:3000/callback"];
+      
+      // Different port should fail
+      expect(isValidRedirectUri("https://app.example.com/callback", authorizedUris)).toBe(false);
+      expect(isValidRedirectUri("https://app.example.com:3000/callback", authorizedUris)).toBe(true);
+      expect(isValidRedirectUri("https://app.example.com:4000/callback", authorizedUris)).toBe(false);
+    });
+
+    test("handles invalid URIs", () => {
+      const authorizedUris = ["not-a-valid-uri", "https://valid.com"];
+      
+      // Invalid redirect URI
+      expect(isValidRedirectUri("not-a-valid-uri", authorizedUris)).toBe(false);
+      
+      // Valid redirect URI with invalid authorized URI should still work if it matches valid one
+      expect(isValidRedirectUri("https://valid.com", authorizedUris)).toBe(true);
+    });
+
+    test("handles empty inputs", () => {
+      expect(isValidRedirectUri("", ["https://app.com"])).toBe(false);
+      expect(isValidRedirectUri("https://app.com", [])).toBe(false);
+    });
+
+    test("prevents open redirect attacks", () => {
+      const authorizedUris = ["https://app.example.com/callback"];
+      
+      // Various attack vectors
+      expect(isValidRedirectUri("https://app.example.com.evil.com/callback", authorizedUris)).toBe(false);
+      expect(isValidRedirectUri("https://app.example.com@evil.com/callback", authorizedUris)).toBe(false);
+      expect(isValidRedirectUri("//evil.com/callback", authorizedUris)).toBe(false);
+      expect(isValidRedirectUri("https:evil.com/callback", authorizedUris)).toBe(false);
+    });
+  });
+});
\ No newline at end of file
diff --git a/src/lib/utils/oauth-validation.ts b/src/lib/utils/oauth-validation.ts
new file mode 100644
index 0000000..3a64b55
--- /dev/null
+++ b/src/lib/utils/oauth-validation.ts
@@ -0,0 +1,59 @@
+/**
+ * Validates a redirect URI against a list of authorized URIs
+ * @param redirectUri The redirect URI to validate
+ * @param authorizedUris List of authorized redirect URIs
+ * @returns true if the redirect URI is authorized, false otherwise
+ */
+export function isValidRedirectUri(redirectUri: string, authorizedUris: string[]): boolean {
+  if (!redirectUri || authorizedUris.length === 0) {
+    return false;
+  }
+
+  try {
+    // Parse the redirect URI to ensure it's valid
+    const redirectUrl = new URL(redirectUri);
+    
+    return authorizedUris.some(authorizedUri => {
+      try {
+        // Handle wildcard paths (e.g., https://example.com/*)
+        if (authorizedUri.endsWith('/*')) {
+          const baseUri = authorizedUri.slice(0, -2);
+          const baseUrl = new URL(baseUri);
+          
+          // Check protocol, host, and port match
+          return redirectUrl.protocol === baseUrl.protocol &&
+                 redirectUrl.host === baseUrl.host &&
+                 redirectUrl.pathname.startsWith(baseUrl.pathname);
+        }
+        
+        // Handle exact match
+        const authorizedUrl = new URL(authorizedUri);
+        
+        // For exact match, everything must match including path and query params
+        return redirectUrl.href === authorizedUrl.href;
+      } catch {
+        // If authorized URI is not a valid URL, treat as invalid
+        return false;
+      }
+    });
+  } catch {
+    // If redirect URI is not a valid URL, it's invalid
+    return false;
+  }
+}
+
+/**
+ * Parses a comma-separated list of redirect URIs and trims whitespace
+ * @param redirectUrls Comma-separated list of redirect URIs
+ * @returns Array of trimmed redirect URIs
+ */
+export function parseRedirectUris(redirectUrls: string): string[] {
+  if (!redirectUrls) {
+    return [];
+  }
+  
+  return redirectUrls
+    .split(',')
+    .map(uri => uri.trim())
+    .filter(uri => uri.length > 0);
+}
\ No newline at end of file
diff --git a/src/pages/api/auth/debug.ts b/src/pages/api/auth/debug.ts
index 5dfdbc6..3267bf2 100644
--- a/src/pages/api/auth/debug.ts
+++ b/src/pages/api/auth/debug.ts
@@ -27,9 +27,13 @@ export const GET: APIRoute = async ({ request }) => {
       headers: { "Content-Type": "application/json" },
     });
   } catch (error) {
+    // Log full error details server-side for debugging
+    console.error("Debug endpoint error:", error);
+    
+    // Only return safe error information to the client
     return new Response(JSON.stringify({
       success: false,
-      error: error instanceof Error ? error.message : "Unknown error",
+      error: error instanceof Error ? error.message : "An unexpected error occurred"
     }), {
       status: 500,
       headers: { "Content-Type": "application/json" },
@@ -60,10 +64,13 @@ export const POST: APIRoute = async ({ request }) => {
       headers: { "Content-Type": "application/json" },
     });
   } catch (error) {
+    // Log full error details server-side for debugging
+    console.error("Debug endpoint error:", error);
+    
+    // Only return safe error information to the client
     return new Response(JSON.stringify({
       success: false,
-      error: error instanceof Error ? error.message : "Unknown error",
-      details: error
+      error: error instanceof Error ? error.message : "An unexpected error occurred"
     }), {
       status: 500,
       headers: { "Content-Type": "application/json" },