diff --git a/core/src/iam/signin.rs b/core/src/iam/signin.rs
index c0a3cfe6..8723c4eb 100644
--- a/core/src/iam/signin.rs
+++ b/core/src/iam/signin.rs
@@ -244,7 +244,8 @@ pub async fn db(
 			session.tk = Some(val.into());
 			session.ns = Some(ns.to_owned());
 			session.db = Some(db.to_owned());
-			session.exp = exp;
+			// TODO(gguillemas): Enforce expiration once session lifetime can be customized.
+			session.exp = None;
 			session.au = Arc::new((&u, Level::Database(ns.to_owned(), db.to_owned())).into());
 			// Check the authentication token
 			match enc {
@@ -296,7 +297,8 @@ pub async fn ns(
 			// Set the authentication on the session
 			session.tk = Some(val.into());
 			session.ns = Some(ns.to_owned());
-			session.exp = exp;
+			// TODO(gguillemas): Enforce expiration once session lifetime can be customized.
+			session.exp = None;
 			session.au = Arc::new((&u, Level::Namespace(ns.to_owned())).into());
 			// Check the authentication token
 			match enc {
@@ -346,7 +348,8 @@ pub async fn root(
 			let enc = encode(&HEADER, &val, &key);
 			// Set the authentication on the session
 			session.tk = Some(val.into());
-			session.exp = exp;
+			// TODO(gguillemas): Enforce expiration once session lifetime can be customized.
+			session.exp = None;
 			session.au = Arc::new((&u, Level::Root).into());
 			// Check the authentication token
 			match enc {
diff --git a/core/src/iam/signup.rs b/core/src/iam/signup.rs
index d316c55a..45fd60cf 100644
--- a/core/src/iam/signup.rs
+++ b/core/src/iam/signup.rs
@@ -70,20 +70,33 @@ pub async fn sc(
 								// Create the authentication key
 								let key = EncodingKey::from_secret(sv.code.as_ref());
 								// Create the authentication claim
+								let exp = Some(
+									match sv.session {
+										Some(v) => {
+											// The defined session duration must be valid
+											match Duration::from_std(v.0) {
+												// The resulting session expiration must be valid
+												Ok(d) => match Utc::now().checked_add_signed(d) {
+													Some(exp) => exp,
+													None => {
+														return Err(Error::InvalidSessionExpiration)
+													}
+												},
+												Err(_) => {
+													return Err(Error::InvalidSessionDuration)
+												}
+											}
+										}
+										_ => Utc::now() + Duration::hours(1),
+									}
+									.timestamp(),
+								);
 								let val = Claims {
 									iss: Some(SERVER_NAME.to_owned()),
 									iat: Some(Utc::now().timestamp()),
 									nbf: Some(Utc::now().timestamp()),
 									jti: Some(Uuid::new_v4().to_string()),
-									exp: Some(
-										match sv.session {
-											Some(v) => {
-												Utc::now() + Duration::from_std(v.0).unwrap()
-											}
-											_ => Utc::now() + Duration::hours(1),
-										}
-										.timestamp(),
-									),
+									exp,
 									ns: Some(ns.to_owned()),
 									db: Some(db.to_owned()),
 									sc: Some(sc.to_owned()),
@@ -100,6 +113,7 @@ pub async fn sc(
 								session.db = Some(db.to_owned());
 								session.sc = Some(sc.to_owned());
 								session.sd = Some(Value::from(rid.to_owned()));
+								session.exp = exp;
 								session.au = Arc::new(Auth::new(Actor::new(
 									rid.to_string(),
 									Default::default(),