diff --git a/pcaps/invalid_ipv6_ext_len.pcap b/pcaps/invalid_ipv6_ext_len.pcap
new file mode 100644
index 00000000..d422033d
Binary files /dev/null and b/pcaps/invalid_ipv6_ext_len.pcap differ
diff --git a/tests/functional/Makefile.am b/tests/functional/Makefile.am
index 5d2ac57a..ae6c58a6 100644
--- a/tests/functional/Makefile.am
+++ b/tests/functional/Makefile.am
@@ -20,7 +20,8 @@ TESTS=basic.sh \
 	ssadetector.sh \
 	vlan.sh \
 	nettisa.sh \
-	mqtt.sh
+	mqtt.sh \
+	invalid_ipv6_ext_len.sh
 
 if WITH_QUIC
 TESTS+=\
@@ -52,6 +53,7 @@ EXTRA_DIST=common.sh \
 	ssadetector.sh \
 	vlan.sh \
 	mqtt.sh \
+	invalid_ipv6_ext_len.sh \
 	reference/basic \
 	reference/basicplus \
 	reference/pstats \
@@ -75,7 +77,8 @@ EXTRA_DIST=common.sh \
 	reference/ssadetector \
 	reference/vlan \
 	reference/nettisa \
-	reference/mqtt
+	reference/mqtt \
+	reference/invalid_ipv6_ext_len
 
 clean-local:
 	rm -rf output
diff --git a/tests/functional/invalid_ipv6_ext_len.sh b/tests/functional/invalid_ipv6_ext_len.sh
new file mode 100755
index 00000000..be2d3214
--- /dev/null
+++ b/tests/functional/invalid_ipv6_ext_len.sh
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+test -z "$srcdir" && export srcdir=.
+
+. $srcdir/pcapreader.sh
+
+run_pcap_reader_test "$pcap_dir/invalid_ipv6_ext_len.pcap" invalid_ipv6_ext_len
+
diff --git a/tests/functional/pcapreader.sh b/tests/functional/pcapreader.sh
new file mode 100755
index 00000000..2c9fdcc0
--- /dev/null
+++ b/tests/functional/pcapreader.sh
@@ -0,0 +1,54 @@
+#!/bin/bash
+
+export LC_ALL=C
+export LANG=C
+
+test -z "$srcdir" && export srcdir=.
+
+ipfixprobe_bin=../../ipfixprobe
+if [ -x ../../../logger/logger ]; then
+   logger_bin=../../../logger/logger
+elif [ -x /usr/local/bin/logger ]; then
+   logger_bin=/usr/local/bin/logger
+else
+   logger_bin=/usr/bin/nemea/logger
+fi
+
+pcap_dir=$srcdir/../../pcaps
+ref_dir=$srcdir/reference
+output_dir=./output
+file_out="$$.data"
+
+# Usage: run_pcap_reader_test <data file> <reference fie>
+run_pcap_reader_test() {
+   if ! [ -f "$ipfixprobe_bin" ]; then
+      echo "ipfixprobe not compiled"
+      return 77
+   fi
+
+   if ! `"$ipfixprobe_bin" -h unirec |head -1 | grep -q '^unirec'`; then
+      echo "compiled without NEMEA"
+      return 77
+   fi
+
+   if ! [ -f "$logger_bin" ]; then
+      echo "logger not compiled"
+      return 77
+   fi
+
+   if ! [ -d "$output_dir" ]; then
+      mkdir "$output_dir"
+   fi
+
+   "$ipfixprobe_bin" -i "pcap;file=$1" -o "unirec;ifc=f:${output_dir}/${file_out}:buffer=off:timeout=WAIT;id=0" >/dev/null
+   "$logger_bin"     -i f:"$output_dir/$file_out" -t | sort > "$output_dir/$2"
+   rm "$output_dir/$file_out"
+
+   if sort "$ref_dir/$2" | diff -u "$output_dir/$2" -s - ; then
+      echo "$2 pcap reader test OK"
+   else
+      echo "$2 pcap reader test FAILED"
+      return 1
+   fi
+}
+
diff --git a/tests/functional/reference/invalid_ipv6_ext_len b/tests/functional/reference/invalid_ipv6_ext_len
new file mode 100644
index 00000000..29199cd3
--- /dev/null
+++ b/tests/functional/reference/invalid_ipv6_ext_len
@@ -0,0 +1,2 @@
+6785:c903::a002:8018:202e:0,1a00:a1a1:a1a1:a1a1:a1a1:a1a1:9ba1:a117,40,0,0,2014-11-10T03:32:08.002213,2014-11-10T03:32:08.002213,00:00:00:00:00:00,00:00:00:00:00:00,1,0,0,0,0,1,0,0
+ipaddr DST_IP,ipaddr SRC_IP,uint64 BYTES,uint64 BYTES_REV,uint64 LINK_BIT_FIELD,time TIME_FIRST,time TIME_LAST,macaddr DST_MAC,macaddr SRC_MAC,uint32 PACKETS,uint32 PACKETS_REV,uint16 DST_PORT,uint16 SRC_PORT,uint8 DIR_BIT_FIELD,uint8 PROTOCOL,uint8 TCP_FLAGS,uint8 TCP_FLAGS_REV