diff --git a/blockcheck2.d/standard/25-fake.sh b/blockcheck2.d/standard/25-fake.sh
index e30af80..121c115 100644
--- a/blockcheck2.d/standard/25-fake.sh
+++ b/blockcheck2.d/standard/25-fake.sh
@@ -100,8 +100,8 @@ pktws_check_https_tls()
 
 	need_fake=0
 
-	ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
-	attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
+	[ "$MAX_TTL" = 0 ] || ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
+	[ "$MAX_AUTOTTL_DELTA" = 0 ] || attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
 
 	ok_any=0
 	ok=0
diff --git a/blockcheck2.d/standard/50-fake-multi.sh b/blockcheck2.d/standard/50-fake-multi.sh
index cc092fe..d2b2d96 100644
--- a/blockcheck2.d/standard/50-fake-multi.sh
+++ b/blockcheck2.d/standard/50-fake-multi.sh
@@ -104,8 +104,8 @@ pktws_check_https_tls()
 		fake=fake_default_tls
 	fi
 
-	ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
-	attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
+	[ "$MAX_TTL" = 0 ] || ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
+	[ "$MAX_AUTOTTL_DELTA" = 0 ] || attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
 
 	# do not test fake + multisplit if multisplit works
 	[ "$need_multisplit" = 0 -a "$SCANLEVEL" != force ] || splitfs=multisplit
diff --git a/blockcheck2.d/standard/55-fake-faked.sh b/blockcheck2.d/standard/55-fake-faked.sh
index 496e3f5..4a0edd6 100644
--- a/blockcheck2.d/standard/55-fake-faked.sh
+++ b/blockcheck2.d/standard/55-fake-faked.sh
@@ -105,8 +105,8 @@ pktws_check_https_tls()
 		fake=fake_default_tls
 	fi
 
-	ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
-	attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
+	[ "$MAX_TTL" = 0 ] || ttls=$(seq -s ' ' $MIN_TTL $MAX_TTL)
+	[ "$MAX_AUTOTTL_DELTA" = 0 ] || attls=$(seq -s ' ' $MIN_AUTOTTL_DELTA $MAX_AUTOTTL_DELTA)
 
 	# do not test fake + fakedsplit if fakedsplit works
 	[ "$need_fakedsplit" = 0 -a "$SCANLEVEL" != force ] || splitfs=fakedsplit