diff --git a/doc/configuration.txt b/doc/configuration.txt
index 3d4aee702..8207067a2 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -10301,10 +10301,10 @@ ssl_bc_protocol : string
   Returns the name of the used protocol when the outgoing connection was made
   over an SSL/TLS transport layer.
 
-ssl_bc_unique_id : string
+ssl_bc_unique_id : binary
   When the outgoing connection was made over an SSL/TLS transport layer,
-  returns a base64 encoded string containing the TLS unique ID as defined
-  in RFC5929 section 3.
+  returns the TLS unique ID as defined in RFC5929 section 3. The unique id
+  can be encoded to base64 using the converter: "ssl_bc_unique_id,base64".
 
 ssl_bc_session_id : binary
   Returns the SSL ID of the back connection when the outgoing connection was
@@ -10513,10 +10513,10 @@ ssl_fc_protocol : string
   Returns the name of the used protocol when the incoming connection was made
   over an SSL/TLS transport layer.
 
-ssl_fc_unique_id : string
+ssl_fc_unique_id : binary
   When the incoming connection was made over an SSL/TLS transport layer,
-  returns a base64 encoded string containing the TLS unique ID as defined
-  in RFC5929 section 3.
+  returns the TLS unique ID as defined in RFC5929 section 3. The unique id
+  can be encoded to base64 using the converter: "ssl_bc_unique_id,base64".
 
 ssl_fc_session_id : binary
   Returns the SSL ID of the front connection when the incoming connection was
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index 19ede3945..229290f86 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -45,7 +45,6 @@
 #include <openssl/err.h>
 #include <openssl/rand.h>
 
-#include <common/base64.h>
 #include <common/buffer.h>
 #include <common/compat.h>
 #include <common/config.h>
@@ -2671,9 +2670,7 @@ smp_fetch_ssl_fc_unique_id(struct proxy *px, struct session *l4, void *l7, unsig
 	int back_conn = (kw[4] == 'b') ? 1 : 0;
 	struct connection *conn;
 	int finished_len;
-	int b64_len;
 	struct chunk *finished_trash;
-	struct chunk *smp_trash;
 
 	smp->flags = 0;
 
@@ -2698,15 +2695,9 @@ smp_fetch_ssl_fc_unique_id(struct proxy *px, struct session *l4, void *l7, unsig
 	if (!finished_len)
 		return 0;
 
-	smp_trash = get_trash_chunk();
-	b64_len = a2base64(finished_trash->str, finished_len, smp_trash->str, smp_trash->size);
-	if (b64_len < 0)
-		return 0;
-
-	smp->data.str.str = smp_trash->str;
-	smp->type = SMP_T_STR;
-	smp->flags |= SMP_F_CONST;
-	smp->data.str.len = b64_len;
+	finished_trash->len = finished_len;
+	smp->data.str = *finished_trash;
+	smp->type = SMP_T_BIN;
 
 	return 1;
 #else
@@ -3411,7 +3402,7 @@ static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
 	{ "ssl_bc_alg_keysize",     smp_fetch_ssl_fc_alg_keysize, 0,                   NULL,    SMP_T_UINT, SMP_USE_L5SRV },
 	{ "ssl_bc_cipher",          smp_fetch_ssl_fc_cipher,      0,                   NULL,    SMP_T_STR,  SMP_USE_L5SRV },
 	{ "ssl_bc_protocol",        smp_fetch_ssl_fc_protocol,    0,                   NULL,    SMP_T_STR,  SMP_USE_L5SRV },
-	{ "ssl_bc_unique_id",       smp_fetch_ssl_fc_unique_id,   0,                   NULL,    SMP_T_STR,  SMP_USE_L5SRV },
+	{ "ssl_bc_unique_id",       smp_fetch_ssl_fc_unique_id,   0,                   NULL,    SMP_T_BIN,  SMP_USE_L5SRV },
 	{ "ssl_bc_use_keysize",     smp_fetch_ssl_fc_use_keysize, 0,                   NULL,    SMP_T_UINT, SMP_USE_L5SRV },
 	{ "ssl_bc_session_id",      smp_fetch_ssl_fc_session_id,  0,                   NULL,    SMP_T_BIN,  SMP_USE_L5SRV },
 	{ "ssl_c_ca_err",           smp_fetch_ssl_c_ca_err,       0,                   NULL,    SMP_T_UINT, SMP_USE_L5CLI },
@@ -3449,7 +3440,7 @@ static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
 	{ "ssl_fc_alpn",            smp_fetch_ssl_fc_alpn,        0,                   NULL,    SMP_T_STR,  SMP_USE_L5CLI },
 #endif
 	{ "ssl_fc_protocol",        smp_fetch_ssl_fc_protocol,    0,                   NULL,    SMP_T_STR,  SMP_USE_L5CLI },
-	{ "ssl_fc_unique_id",       smp_fetch_ssl_fc_unique_id,   0,                   NULL,    SMP_T_STR,  SMP_USE_L5CLI },
+	{ "ssl_fc_unique_id",       smp_fetch_ssl_fc_unique_id,   0,                   NULL,    SMP_T_BIN,  SMP_USE_L5CLI },
 	{ "ssl_fc_use_keysize",     smp_fetch_ssl_fc_use_keysize, 0,                   NULL,    SMP_T_UINT, SMP_USE_L5CLI },
 	{ "ssl_fc_session_id",      smp_fetch_ssl_fc_session_id,  0,                   NULL,    SMP_T_BIN,  SMP_USE_L5CLI },
 	{ "ssl_fc_sni",             smp_fetch_ssl_fc_sni,         0,                   NULL,    SMP_T_STR,  SMP_USE_L5CLI },