diff --git a/src/sim/class_tables.c b/src/sim/class_tables.c
index 29ef2d7f9..3d5052132 100644
--- a/src/sim/class_tables.c
+++ b/src/sim/class_tables.c
@@ -178,6 +178,7 @@ static int gp_cla_ins_helper(const struct osim_cla_ins_case *cic,
 {
 	uint8_t ins = hdr[1];
 	uint8_t p1 = hdr[2];
+	uint8_t p3 = hdr[4];
 
 	switch (ins) {
 	case 0xE2:	/* STORE DATA */
@@ -197,6 +198,16 @@ static int gp_cla_ins_helper(const struct osim_cla_ins_case *cic,
 		else
 			return 2; /* ETSI TS 102 221 V16.2.0 11.1.2 */
 		break;
+	case 0xCA:
+	case 0xCB:
+		/* in their infinite wisdom, GlobalPlatform made GET DATA a command that can be either APDU
+		 * case 2 or case 4.  As the specify Le must be 0x00, we can conclude that P3 == 0x00 must be
+		 * Le, while P3 != 0x00 must be Lc and hence case 4 */
+		if (p3 == 0x00)
+			return 2;
+		else
+			return 4;
+		break;
 	}
 	return 0;
 }
@@ -225,8 +236,8 @@ static const uint8_t uicc_ins_tbl_80[256] = {
 static const uint8_t gp_ins_tbl_8ce[256] = {
 	[0xE4]		= 4,	/* DELETE */
 	[0xE2]		= 0x80,	/* STORE DATA */
-	[0xCA]		= 4,	/* GET DATA */
-	[0xCB]		= 4,	/* GET DATA */
+	[0xCA]		= 0x80,	/* GET DATA */
+	[0xCB]		= 0x80,	/* GET DATA */
 	[0xF2]		= 0x80,	/* GET STATUS */
 	[0xE6]		= 4,	/* INSTALL */
 	[0xE8]		= 4,	/* LOAD */
diff --git a/tests/sim/sim_test.c b/tests/sim/sim_test.c
index 9a52af47f..ab5d2be36 100644
--- a/tests/sim/sim_test.c
+++ b/tests/sim/sim_test.c
@@ -29,6 +29,8 @@ const uint8_t uicc_read[] = { 0x00, 0xB0, 0x00, 0x00, 0x10 };
 const uint8_t uicc_upd[] = { 0x00, 0xD6, 0x00, 0x00, 0x02, 0x01, 0x02 };
 const uint8_t uicc_get_status[] = { 0x80, 0xf2, 0x00, 0x02, 0x10 };
 const uint8_t euicc_m2m_get_status[] = { 0x81, 0xf2, 0x40, 0x02, 0x02, 0x4f, 0x00 };
+const uint8_t gp_get_data2[] = { 0x81, 0xCA, 0x00, 0x5A, 0x00 };
+const uint8_t gp_get_data4[] = { 0x81, 0xCA, 0x00, 0x5A, 0x12 };
 
 #define APDU_CASE_ASSERT(x, y)				\
 	do {						\
@@ -49,6 +51,8 @@ static void test_cla_ins_tbl(void)
 	APDU_CASE_ASSERT(uicc_upd, 3);
 	APDU_CASE_ASSERT(uicc_get_status, 2);
 	APDU_CASE_ASSERT(euicc_m2m_get_status, 4);
+	APDU_CASE_ASSERT(gp_get_data2, 2);
+	APDU_CASE_ASSERT(gp_get_data4, 4);
 }
 
 int main(int argc, char **argv)
diff --git a/tests/sim/sim_test.ok b/tests/sim/sim_test.ok
index cac59ba0e..3abfb7186 100644
--- a/tests/sim/sim_test.ok
+++ b/tests/sim/sim_test.ok
@@ -6,3 +6,5 @@ Testing uicc_read
 Testing uicc_upd
 Testing uicc_get_status
 Testing euicc_m2m_get_status
+Testing gp_get_data2
+Testing gp_get_data4