diff --git a/src/charon-cmd/cmd/cmd_connection.c b/src/charon-cmd/cmd/cmd_connection.c
index 8e8d8236e..e220e33a6 100644
--- a/src/charon-cmd/cmd/cmd_connection.c
+++ b/src/charon-cmd/cmd/cmd_connection.c
@@ -585,7 +585,7 @@ cmd_connection_t *cmd_connection_create()
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio(
 			(callback_job_cb_t)initiate, this, NULL,
-			(callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+			callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 
 	return &this->public;
 }
diff --git a/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_dns_proxy.c b/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_dns_proxy.c
index caaa2ff05..cc15bd40f 100644
--- a/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_dns_proxy.c
+++ b/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_dns_proxy.c
@@ -340,7 +340,7 @@ METHOD(android_dns_proxy_t, handle, bool,
 						  skt);
 		lib->scheduler->schedule_job(lib->scheduler,
 			(job_t*)callback_job_create(handle_timeout, skt,
-					NULL, (callback_job_cancel_t)return_false), SOCKET_TIMEOUT);
+					NULL, callback_job_cancel_thread), SOCKET_TIMEOUT);
 	}
 	skt->last_use = time_monotonic(NULL);
 	if (sendto(skt->fd, data.ptr, data.len, 0, dst->get_sockaddr(dst),
diff --git a/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_service.c b/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_service.c
index f7e6ec34b..12d2e681b 100644
--- a/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_service.c
+++ b/src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_service.c
@@ -359,7 +359,7 @@ static bool setup_tun_device(private_android_service_t *this,
 
 		lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create((callback_job_cb_t)handle_plain, this,
-									NULL, (callback_job_cancel_t)return_false));
+									NULL, callback_job_cancel_thread));
 	}
 	return TRUE;
 }
@@ -600,7 +600,7 @@ METHOD(listener_t, alert, bool,
 				lib->processor->queue_job(lib->processor,
 					(job_t*)callback_job_create_with_prio(
 						(callback_job_cb_t)reestablish, id, free,
-						(callback_job_cancel_t)return_false, JOB_PRIO_HIGH));
+						callback_job_cancel_thread, JOB_PRIO_HIGH));
 				break;
 			}
 			case ALERT_PEER_INIT_UNREACHABLE:
@@ -619,7 +619,7 @@ METHOD(listener_t, alert, bool,
 					lib->processor->queue_job(lib->processor,
 						(job_t*)callback_job_create_with_prio(
 							(callback_job_cb_t)terminate, id, free,
-							(callback_job_cancel_t)return_false, JOB_PRIO_HIGH));
+							callback_job_cancel_thread, JOB_PRIO_HIGH));
 					stay_registered = FALSE;
 				}
 				else
diff --git a/src/libcharon/network/receiver.c b/src/libcharon/network/receiver.c
index e79d59744..480d1d622 100644
--- a/src/libcharon/network/receiver.c
+++ b/src/libcharon/network/receiver.c
@@ -737,7 +737,7 @@ receiver_t *receiver_create()
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)receive_packets,
-			this, NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+			this, NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 
 	return &this->public;
 }
diff --git a/src/libcharon/network/sender.c b/src/libcharon/network/sender.c
index 4543766d6..3fcd17f1b 100644
--- a/src/libcharon/network/sender.c
+++ b/src/libcharon/network/sender.c
@@ -216,7 +216,7 @@ sender_t * sender_create()
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)send_packets,
-			this, NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+			this, NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 
 	return &this->public;
 }
diff --git a/src/libcharon/plugins/bypass_lan/bypass_lan_listener.c b/src/libcharon/plugins/bypass_lan/bypass_lan_listener.c
index db7abd814..c9aed3666 100644
--- a/src/libcharon/plugins/bypass_lan/bypass_lan_listener.c
+++ b/src/libcharon/plugins/bypass_lan/bypass_lan_listener.c
@@ -227,7 +227,7 @@ METHOD(kernel_listener_t, roam, bool,
 {
 	lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create((callback_job_cb_t)update_bypass, this,
-									NULL, (callback_job_cancel_t)return_false));
+									NULL, callback_job_cancel_thread));
 	return TRUE;
 }
 
@@ -269,7 +269,7 @@ METHOD(bypass_lan_listener_t, reload_interfaces, void,
 	this->mutex->unlock(this->mutex);
 	lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create((callback_job_cb_t)update_bypass, this,
-									NULL, (callback_job_cancel_t)return_false));
+									NULL, callback_job_cancel_thread));
 }
 
 METHOD(bypass_lan_listener_t, destroy, void,
diff --git a/src/libcharon/plugins/eap_radius/eap_radius_accounting.c b/src/libcharon/plugins/eap_radius/eap_radius_accounting.c
index f833dc3c0..2f29d0807 100644
--- a/src/libcharon/plugins/eap_radius/eap_radius_accounting.c
+++ b/src/libcharon/plugins/eap_radius/eap_radius_accounting.c
@@ -706,7 +706,7 @@ static void schedule_interim(private_eap_radius_accounting_t *this,
 			(job_t*)callback_job_create_with_prio(
 				(callback_job_cb_t)send_interim,
 				data, (void*)destroy_interim_data,
-				(callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL), tv);
+				callback_job_cancel_thread, JOB_PRIO_CRITICAL), tv);
 	}
 }
 
diff --git a/src/libcharon/plugins/eap_radius/eap_radius_plugin.c b/src/libcharon/plugins/eap_radius/eap_radius_plugin.c
index 505154261..55d5e032c 100644
--- a/src/libcharon/plugins/eap_radius/eap_radius_plugin.c
+++ b/src/libcharon/plugins/eap_radius/eap_radius_plugin.c
@@ -445,7 +445,7 @@ void eap_radius_handle_timeout(ike_sa_id_t *id)
 		lib->processor->queue_job(lib->processor,
 				(job_t*)callback_job_create_with_prio(
 						(callback_job_cb_t)delete_all_async, NULL, NULL,
-						(callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+						callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 	}
 	else if (id)
 	{
diff --git a/src/libcharon/plugins/ha/ha_ctl.c b/src/libcharon/plugins/ha/ha_ctl.c
index 8859bae16..3d2ac7de8 100644
--- a/src/libcharon/plugins/ha/ha_ctl.c
+++ b/src/libcharon/plugins/ha/ha_ctl.c
@@ -199,6 +199,6 @@ ha_ctl_t *ha_ctl_create(ha_segments_t *segments, ha_cache_t *cache)
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)dispatch_fifo,
-			this, NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+			this, NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 	return &this->public;
 }
diff --git a/src/libcharon/plugins/ha/ha_dispatcher.c b/src/libcharon/plugins/ha/ha_dispatcher.c
index 5de26a65a..83be91ab1 100644
--- a/src/libcharon/plugins/ha/ha_dispatcher.c
+++ b/src/libcharon/plugins/ha/ha_dispatcher.c
@@ -1184,7 +1184,7 @@ ha_dispatcher_t *ha_dispatcher_create(ha_socket_t *socket,
 	);
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)dispatch, this,
-				NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+				NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 
 	return &this->public;
 }
diff --git a/src/libcharon/plugins/ha/ha_segments.c b/src/libcharon/plugins/ha/ha_segments.c
index afb76b39e..32d9ee407 100644
--- a/src/libcharon/plugins/ha/ha_segments.c
+++ b/src/libcharon/plugins/ha/ha_segments.c
@@ -316,7 +316,7 @@ static void start_watchdog(private_ha_segments_t *this)
 	this->heartbeat_active = TRUE;
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)watchdog, this,
-				NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+				NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 }
 
 METHOD(ha_segments_t, handle_status, void,
@@ -404,7 +404,7 @@ static void start_heartbeat(private_ha_segments_t *this)
 {
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)send_status,
-			this, NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+			this, NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 }
 
 /**
@@ -451,7 +451,7 @@ static void start_autobalance(private_ha_segments_t *this)
 	DBG1(DBG_CFG, "scheduling HA autobalance every %ds", this->autobalance);
 	lib->scheduler->schedule_job(lib->scheduler,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)autobalance,
-			this, NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL),
+			this, NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL),
 		this->autobalance);
 }
 
diff --git a/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_esp_handler.c b/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_esp_handler.c
index 095ad67b4..c18e266e4 100644
--- a/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_esp_handler.c
+++ b/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_esp_handler.c
@@ -337,7 +337,7 @@ kernel_libipsec_esp_handler_t *kernel_libipsec_esp_handler_create()
 	}
 	lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create(send_esp, this, NULL,
-										(callback_job_cancel_t)return_false));
+										callback_job_cancel_thread));
 	return &this->public;
 }
 
diff --git a/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_router.c b/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_router.c
index 74746e251..07adc70be 100644
--- a/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_router.c
+++ b/src/libcharon/plugins/kernel_libipsec/kernel_libipsec_router.c
@@ -364,7 +364,7 @@ kernel_libipsec_router_t *kernel_libipsec_router_create()
 	charon->receiver->add_esp_cb(charon->receiver, receiver_esp_cb, NULL);
 	lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create((callback_job_cb_t)handle_plain, this,
-									NULL, (callback_job_cancel_t)return_false));
+										NULL, callback_job_cancel_thread));
 
 	router = &this->public;
 	return &this->public;
diff --git a/src/libcharon/plugins/smp/smp.c b/src/libcharon/plugins/smp/smp.c
index 6ca9f1399..85ff5830b 100644
--- a/src/libcharon/plugins/smp/smp.c
+++ b/src/libcharon/plugins/smp/smp.c
@@ -710,7 +710,7 @@ static job_requeue_t dispatch(private_smp_t *this)
 	fdp = malloc_thing(int);
 	*fdp = fd;
 	job = callback_job_create((callback_job_cb_t)process, fdp, free,
-							  (callback_job_cancel_t)return_false);
+							  callback_job_cancel_thread);
 	lib->processor->queue_job(lib->processor, (job_t*)job);
 
 	return JOB_REQUEUE_DIRECT;
@@ -800,7 +800,7 @@ plugin_t *smp_plugin_create()
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create_with_prio((callback_job_cb_t)dispatch, this,
-				NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+				NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 
 	return &this->public.plugin;
 }
diff --git a/src/libcharon/plugins/tnc_pdp/tnc_pdp_connections.c b/src/libcharon/plugins/tnc_pdp/tnc_pdp_connections.c
index 30aeb116d..da317a894 100644
--- a/src/libcharon/plugins/tnc_pdp/tnc_pdp_connections.c
+++ b/src/libcharon/plugins/tnc_pdp/tnc_pdp_connections.c
@@ -210,7 +210,7 @@ METHOD(tnc_pdp_connections_t, add, void,
 	/* schedule timeout checking */
 	lib->scheduler->schedule_job_ms(lib->scheduler,
 				(job_t*)callback_job_create((callback_job_cb_t)check_timeouts,
-					this, NULL, (callback_job_cancel_t)return_false),
+					this, NULL, callback_job_cancel_thread),
 				this->timeout * 1000);
 
 	dbg_nas_user(nas_id, user_name, FALSE, "created");
diff --git a/src/libcharon/plugins/uci/uci_control.c b/src/libcharon/plugins/uci/uci_control.c
index b033c832c..8074005ee 100644
--- a/src/libcharon/plugins/uci/uci_control.c
+++ b/src/libcharon/plugins/uci/uci_control.c
@@ -296,7 +296,7 @@ uci_control_t *uci_control_create()
 	{
 		lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create_with_prio((callback_job_cb_t)receive,
-							this, NULL, (callback_job_cancel_t)return_false,
+							this, NULL, callback_job_cancel_thread,
 							JOB_PRIO_CRITICAL));
 	}
 	return &this->public;
diff --git a/src/libipsec/ipsec_event_relay.c b/src/libipsec/ipsec_event_relay.c
index 0f10795d1..802146eef 100644
--- a/src/libipsec/ipsec_event_relay.c
+++ b/src/libipsec/ipsec_event_relay.c
@@ -230,7 +230,7 @@ ipsec_event_relay_t *ipsec_event_relay_create()
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create((callback_job_cb_t)handle_events, this,
-			NULL, (callback_job_cancel_t)return_false));
+			NULL, callback_job_cancel_thread));
 
 	return &this->public;
 }
diff --git a/src/libipsec/ipsec_processor.c b/src/libipsec/ipsec_processor.c
index 2572b0880..8549fefe2 100644
--- a/src/libipsec/ipsec_processor.c
+++ b/src/libipsec/ipsec_processor.c
@@ -336,9 +336,9 @@ ipsec_processor_t *ipsec_processor_create()
 
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create((callback_job_cb_t)process_inbound, this,
-									NULL, (callback_job_cancel_t)return_false));
+									NULL, callback_job_cancel_thread));
 	lib->processor->queue_job(lib->processor,
 		(job_t*)callback_job_create((callback_job_cb_t)process_outbound, this,
-									NULL, (callback_job_cancel_t)return_false));
+									NULL, callback_job_cancel_thread));
 	return &this->public;
 }
diff --git a/src/libpttls/pt_tls_dispatcher.c b/src/libpttls/pt_tls_dispatcher.c
index a134bee23..c7e42b277 100644
--- a/src/libpttls/pt_tls_dispatcher.c
+++ b/src/libpttls/pt_tls_dispatcher.c
@@ -156,7 +156,7 @@ METHOD(pt_tls_dispatcher_t, dispatch, void,
 		lib->processor->queue_job(lib->processor,
 				(job_t*)callback_job_create_with_prio((callback_job_cb_t)handle,
 										connection, (void*)cleanup,
-										(callback_job_cancel_t)return_false,
+										callback_job_cancel_thread,
 										JOB_PRIO_CRITICAL));
 	}
 }
diff --git a/src/libstrongswan/networking/streams/stream_service.c b/src/libstrongswan/networking/streams/stream_service.c
index 5b709a224..c85a06643 100644
--- a/src/libstrongswan/networking/streams/stream_service.c
+++ b/src/libstrongswan/networking/streams/stream_service.c
@@ -221,7 +221,7 @@ static bool watch(private_stream_service_t *this, int fd, watcher_event_t event)
 
 		lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create_with_prio((void*)accept_async, data,
-				(void*)destroy_async_data, (callback_job_cancel_t)return_false,
+				(void*)destroy_async_data, callback_job_cancel_thread,
 				this->prio));
 	}
 	else
diff --git a/src/libstrongswan/processing/jobs/callback_job.c b/src/libstrongswan/processing/jobs/callback_job.c
index cb2a0aba5..3ab40b947 100644
--- a/src/libstrongswan/processing/jobs/callback_job.c
+++ b/src/libstrongswan/processing/jobs/callback_job.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 Tobias Brunner
+ * Copyright (C) 2009-2025 Tobias Brunner
  * Copyright (C) 2007-2011 Martin Willi
  *
  * Copyright (C) secunet Security Networks AG
@@ -131,3 +131,11 @@ callback_job_t *callback_job_create(callback_job_cb_t cb, void *data,
 	return callback_job_create_with_prio(cb, data, cleanup, cancel,
 										 JOB_PRIO_MEDIUM);
 }
+
+/*
+ * Described in header
+ */
+bool callback_job_cancel_thread(void *data)
+{
+	return FALSE;
+}
diff --git a/src/libstrongswan/processing/jobs/callback_job.h b/src/libstrongswan/processing/jobs/callback_job.h
index 0f1ae212d..fda868879 100644
--- a/src/libstrongswan/processing/jobs/callback_job.h
+++ b/src/libstrongswan/processing/jobs/callback_job.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012-2025 Tobias Brunner
  * Copyright (C) 2007-2011 Martin Willi
  *
  * Copyright (C) secunet Security Networks AG
@@ -62,6 +62,15 @@ typedef void (*callback_job_cleanup_t)(void *data);
  */
 typedef bool (*callback_job_cancel_t)(void *data);
 
+/**
+ * Default implementation of callback_job_cancel_t that simply returns FALSE
+ * to force cancellation of the thread by the processor.
+ *
+ * @param data			ignored argument
+ * @return				always returns FALSE
+ */
+bool callback_job_cancel_thread(void *data);
+
 /**
  * Class representing an callback Job.
  *
diff --git a/src/libstrongswan/processing/scheduler.c b/src/libstrongswan/processing/scheduler.c
index c5e5dd83e..76d98ddff 100644
--- a/src/libstrongswan/processing/scheduler.c
+++ b/src/libstrongswan/processing/scheduler.c
@@ -329,7 +329,8 @@ scheduler_t * scheduler_create()
 	this->heap = (event_t**)calloc(this->heap_size + 1, sizeof(event_t*));
 
 	job = callback_job_create_with_prio((callback_job_cb_t)schedule, this,
-										NULL, return_false, JOB_PRIO_CRITICAL);
+										NULL, callback_job_cancel_thread,
+										JOB_PRIO_CRITICAL);
 	lib->processor->queue_job(lib->processor, (job_t*)job);
 
 	return &this->public;
diff --git a/src/libstrongswan/processing/watcher.c b/src/libstrongswan/processing/watcher.c
index 1200d6709..a86ec0910 100644
--- a/src/libstrongswan/processing/watcher.c
+++ b/src/libstrongswan/processing/watcher.c
@@ -291,7 +291,7 @@ static void notify(private_watcher_t *this, entry_t *entry,
 
 	this->jobs->insert_last(this->jobs,
 					callback_job_create_with_prio((void*)notify_async, data,
-						(void*)notify_end, (callback_job_cancel_t)return_false,
+						(void*)notify_end, callback_job_cancel_thread,
 						JOB_PRIO_CRITICAL));
 }
 
@@ -559,7 +559,7 @@ METHOD(watcher_t, add, void,
 
 		lib->processor->queue_job(lib->processor,
 			(job_t*)callback_job_create_with_prio((void*)watch, this,
-				NULL, (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
+				NULL, callback_job_cancel_thread, JOB_PRIO_CRITICAL));
 	}
 	else
 	{
diff --git a/src/libtls/tests/suites/test_socket.c b/src/libtls/tests/suites/test_socket.c
index 91ee58b97..c17d0a887 100644
--- a/src/libtls/tests/suites/test_socket.c
+++ b/src/libtls/tests/suites/test_socket.c
@@ -587,7 +587,7 @@ static void start_echo_server(echo_server_config_t *config)
 
 	lib->processor->queue_job(lib->processor, (job_t*)
 				callback_job_create((void*)serve_echo, config, NULL,
-									(callback_job_cancel_t)return_false));
+									callback_job_cancel_thread));
 }
 
 /**