diff --git a/src/libCom/osi/os/default/osdThreadHooks.c b/src/libCom/osi/os/default/osdThreadHooks.c
index cbe28a4ff..3c2f49667 100644
--- a/src/libCom/osi/os/default/osdThreadHooks.c
+++ b/src/libCom/osi/os/default/osdThreadHooks.c
@@ -72,6 +72,7 @@ epicsShareFunc int epicsThreadHookAdd(EPICS_THREAD_HOOK_ROUTINE hook)
         return 0;
     }
     fprintf(stderr, "epicsThreadHookAdd: Locking problem\n");
+    free(pHook);
     return -1;
 }