crates/adapters/auth/src/lib.rs

@@ -95,7 +95,7 @@ mod tests {
 
     #[test]
     fn generate_and_validate_token() {
-        let svc = JwtAuthService::new("secret".into(), 3600);
+        let svc = JwtAuthService::new("a-secret-that-is-at-least-32-bytes!!".into(), 3600);
         let id = UserId::new();
         let tok = svc.generate_token(&id).unwrap();
         let parsed = svc.validate_token(&tok.token).unwrap();
@@ -104,7 +104,7 @@ mod tests {
 
     #[test]
     fn invalid_token_returns_unauthorized() {
-        let svc = JwtAuthService::new("secret".into(), 3600);
+        let svc = JwtAuthService::new("a-secret-that-is-at-least-32-bytes!!".into(), 3600);
         let err = svc.validate_token("not.a.token").unwrap_err();
         assert!(matches!(err, DomainError::Unauthorized));
     }

crates/application/src/use_cases/auth.rs

@@ -64,10 +64,15 @@ pub async fn login(
     input: LoginInput,
 ) -> Result<LoginOutput, DomainError> {
     let email = Email::new(input.email)?;
-    let user = users
-        .find_by_email(&email)
-        .await?
-        .ok_or(DomainError::Unauthorized)?;
+    let user = users.find_by_email(&email).await?;
+    if user.is_none() {
+        // Timing equalization — prevents email enumeration via response-time oracle.
+        // Running the hasher on a miss makes "no such user" take the same time as
+        // "wrong password", so attackers cannot distinguish the two cases.
+        let _ = hasher.hash(&input.password).await;
+        return Err(DomainError::Unauthorized);
+    }
+    let user = user.unwrap();
     if !hasher.verify(&input.password, &user.password_hash).await? {
         return Err(DomainError::Unauthorized);
     }

crates/bootstrap/src/factory.rs

@@ -1,4 +1,5 @@
-const JWT_TTL_SECS: i64 = 86_400 * 30;
+const JWT_TTL_SECS: i64 = 86_400; // 24 hours (was 30 days)
+const JWT_SECRET_MIN_BYTES: usize = 32; // 256 bits minimum for HS256
 
 use async_trait::async_trait;
 use sqlx::PgPool;
@@ -107,10 +108,16 @@ pub async fn build(cfg: &Config) -> Infrastructure {
         )),
         feed: Arc::new(postgres::feed::PgFeedRepository::new(pool.clone())),
         search: Arc::new(postgres_search::PgSearchRepository::new(pool.clone())),
-        auth: Arc::new(auth::JwtAuthService::new(
-            cfg.jwt_secret.clone(),
-            JWT_TTL_SECS,
-        )),
+        auth: Arc::new({
+            if cfg.jwt_secret.len() < JWT_SECRET_MIN_BYTES {
+                panic!(
+                    "JWT_SECRET is {} bytes — minimum is {} bytes for HS256 security",
+                    cfg.jwt_secret.len(),
+                    JWT_SECRET_MIN_BYTES,
+                );
+            }
+            auth::JwtAuthService::new(cfg.jwt_secret.clone(), JWT_TTL_SECS)
+        }),
         hasher: Arc::new(auth::Argon2PasswordHasher),
         events: event_publisher,
         federation: ap_service.clone() as Arc<dyn domain::ports::FederationActionPort>,