Index: lib/Driver/SanitizerArgs.cpp
===================================================================
--- lib/Driver/SanitizerArgs.cpp
+++ lib/Driver/SanitizerArgs.cpp
@@ -93,7 +93,8 @@
       {Memory, "msan_blacklist.txt"},
       {Thread, "tsan_blacklist.txt"},
       {DataFlow, "dfsan_abilist.txt"},
-      {CFI, "cfi_blacklist.txt"}};
+      {CFI, "cfi_blacklist.txt"},
+      {Undefined | Integer | Nullability, "ubsan_blacklist.txt"}};
   for (const auto &BL : DefaultBlacklists) {
     if (!(Kinds & BL.first))
       continue;
Index: test/Driver/fsanitize-blacklist.c
===================================================================
--- test/Driver/fsanitize-blacklist.c
+++ test/Driver/fsanitize-blacklist.c
@@ -30,9 +30,10 @@
 
 // Check that we can add multiple default blacklists if the matching sanitizers
 // are enabled.
-// RUN: %clang -target x86_64-linux-gnu -fsanitize=address,cfi -flto -fvisibility=hidden -resource-dir=%S/Inputs/resource_dir %s -### 2>&1 | FileCheck %s --check-prefix=MULTIPLE-DEFAULT-BLACKLISTS
+// RUN: %clang -target x86_64-linux-gnu -fsanitize=address,cfi,undefined -flto -fvisibility=hidden -resource-dir=%S/Inputs/resource_dir %s -### 2>&1 | FileCheck %s --check-prefix=MULTIPLE-DEFAULT-BLACKLISTS
 // MULTIPLE-DEFAULT-BLACKLISTS-DAG: -fsanitize-blacklist={{.*}}asan_blacklist.txt
 // MULTIPLE-DEFAULT-BLACKLISTS-DAG: -fsanitize-blacklist={{.*}}cfi_blacklist.txt
+// MULTIPLE-DEFAULT-BLACKLISTS-DAG: -fsanitize-blacklist={{.*}}ubsan_blacklist.txt
 
 // Ignore -fsanitize-blacklist flag if there is no -fsanitize flag.
 // RUN: %clang -target x86_64-linux-gnu -fsanitize-blacklist=%t.good %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-NO-SANITIZE --check-prefix=DELIMITERS