diff --git a/libc/fmt/vcscanf.c b/libc/fmt/vcscanf.c
index 22aa93a26..3002113b9 100644
--- a/libc/fmt/vcscanf.c
+++ b/libc/fmt/vcscanf.c
@@ -174,6 +174,8 @@ int vcscanf(int callback(void *), int unget(int, void *), void *arg,
           c = callback(arg);
           if (c == prefix || c == prefix + ('a' - 'A')) {
             c = callback(arg);
+          } else if (c == -1) {
+            c = '0';
           }
         }
       DecodeNumber:
diff --git a/test/libc/fmt/sscanf_test.c b/test/libc/fmt/sscanf_test.c
index 245c6fe86..399f7b604 100644
--- a/test/libc/fmt/sscanf_test.c
+++ b/test/libc/fmt/sscanf_test.c
@@ -231,3 +231,31 @@ TEST(sscanf, testInttypes_macros) {
   ASSERT_EQ(if64, 1);
   ASSERT_EQ(uf64, 1);
 }
+
+TEST(sscanf, test0) {
+  int v;
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%x", &v), 1);
+  ASSERT_EQ(v, 0);
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%X", &v), 1);
+  ASSERT_EQ(v, 0);
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%d", &v), 1);
+  ASSERT_EQ(v, 0);
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%o", &v), 1);
+  ASSERT_EQ(v, 0);
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%u", &v), 1);
+  ASSERT_EQ(v, 0);
+
+  v = 0xFFFFFFFF;
+  ASSERT_EQ(sscanf("0", "%b", &v), 1);
+  ASSERT_EQ(v, 0);
+}