diff --git a/0001-pkcs15-regression-in-e35febe-compute-cert-length.patch b/0001-pkcs15-regression-in-e35febe-compute-cert-length.patch
new file mode 100644
index 0000000..f00bce0
--- /dev/null
+++ b/0001-pkcs15-regression-in-e35febe-compute-cert-length.patch
@@ -0,0 +1,114 @@
+From cc5a171ddcc8e49b2252135daac9ad3aa6d66ae7 Mon Sep 17 00:00:00 2001
+From: Viktor Tarasov <viktor.tarasov@gmail.com>
+Date: Tue, 25 Dec 2012 20:05:45 +0100
+Subject: [PATCH] pkcs15: regression in e35febe: compute cert length
+
+parse_x509_cert() reviewed.
+Now certificate's DER data are allocated and the DER data length is determined in one place.
+
+https://github.com/OpenSC/OpenSC/pull/114
+https://github.com/OpenSC/OpenSC/commit/e35febe
+---
+ src/libopensc/pkcs15-cert.c | 37 +++++++++++++++++++------------------
+ 1 file changed, 19 insertions(+), 18 deletions(-)
+
+diff --git a/src/libopensc/pkcs15-cert.c b/src/libopensc/pkcs15-cert.c
+index 86bea25..9b08aac 100644
+--- a/src/libopensc/pkcs15-cert.c
++++ b/src/libopensc/pkcs15-cert.c
+@@ -34,13 +34,13 @@
+ #include "pkcs15.h"
+ 
+ static int
+-parse_x509_cert(sc_context_t *ctx, const u8 *buf, size_t buflen, struct sc_pkcs15_cert *cert)
++parse_x509_cert(sc_context_t *ctx, struct sc_pkcs15_der *der, struct sc_pkcs15_cert *cert)
+ {
+ 	int r;
+ 	struct sc_algorithm_id sig_alg;
+-	struct sc_pkcs15_pubkey  * pubkey = NULL;
+-	u8 *serial = NULL;
+-	size_t serial_len = 0;
++	struct sc_pkcs15_pubkey *pubkey = NULL;
++	unsigned char *serial = NULL, *buf =  der->value;
++	size_t serial_len = 0, data_len = 0, buflen = der->len;
+ 	struct sc_asn1_entry asn1_version[] = {
+ 		{ "version", SC_ASN1_INTEGER, SC_ASN1_TAG_INTEGER, 0, &cert->version, NULL },
+ 		{ NULL, 0, 0, 0, NULL, NULL }
+@@ -87,30 +87,32 @@ parse_x509_cert(sc_context_t *ctx, const u8 *buf, size_t buflen, struct sc_pkcs1
+ 	if (obj == NULL)
+ 		LOG_TEST_RET(ctx, SC_ERROR_INVALID_ASN1_OBJECT, "X.509 certificate not found");
+ 
+-	cert->data.len = objlen + (obj - buf);
++	data_len = objlen + (obj - buf);
++	cert->data.value = malloc(data_len);
++	if (!cert->data.value)
++		LOG_FUNC_RETURN(ctx, SC_ERROR_OUT_OF_MEMORY);
++	memcpy(cert->data.value, buf, data_len);
++	cert->data.len = data_len;
++
+ 	r = sc_asn1_decode(ctx, asn1_cert, obj, objlen, NULL, NULL);
+ 	LOG_TEST_RET(ctx, r, "ASN.1 parsing of certificate failed");
+ 
+ 	cert->version++;
+ 
+-	if (pubkey) {
+-		cert->key = pubkey;
+-		pubkey = NULL;
+-	}
+-	else {
++	if (!pubkey)
+ 		LOG_TEST_RET(ctx, SC_ERROR_INVALID_ASN1_OBJECT, "Unable to decode subjectPublicKeyInfo from cert");
+-	}
++	cert->key = pubkey;
++
+ 	sc_asn1_clear_algorithm_id(&sig_alg);
+-	if (r < 0)
+-		return r;
+ 
+ 	if (serial && serial_len)   {
+ 		sc_format_asn1_entry(asn1_serial_number + 0, serial, &serial_len, 1);
+ 		r = sc_asn1_encode(ctx, asn1_serial_number, &cert->serial, &cert->serial_len);
+ 		free(serial);
++		LOG_TEST_RET(ctx, r, "ASN.1 encoding of serial failed");
+ 	}
+ 
+-	return r;
++	return SC_SUCCESS;
+ }
+ 
+ 
+@@ -125,7 +127,7 @@ sc_pkcs15_pubkey_from_cert(struct sc_context *ctx,
+ 	if (cert == NULL)
+ 		return SC_ERROR_OUT_OF_MEMORY;
+ 
+-	rv = parse_x509_cert(ctx, cert_blob->value, cert_blob->len, cert);
++	rv = parse_x509_cert(ctx, cert_blob, cert);
+ 
+ 	*out = cert->key;
+ 	cert->key = NULL;
+@@ -158,20 +160,19 @@ sc_pkcs15_read_certificate(struct sc_pkcs15_card *p15card, const struct sc_pkcs1
+ 		return SC_ERROR_OBJECT_NOT_FOUND;
+ 	}
+ 
+-
+ 	cert = malloc(sizeof(struct sc_pkcs15_cert));
+ 	if (cert == NULL) {
+ 		free(der.value);
+ 		return SC_ERROR_OUT_OF_MEMORY;
+ 	}
+ 	memset(cert, 0, sizeof(struct sc_pkcs15_cert));
+-	if (parse_x509_cert(p15card->card->ctx, der.value, der.len, cert)) {
++	if (parse_x509_cert(p15card->card->ctx, &der, cert)) {
+ 		free(der.value);
+ 		sc_pkcs15_free_certificate(cert);
+ 		return SC_ERROR_INVALID_ASN1_OBJECT;
+ 	}
++	free(der.value);
+ 
+-	cert->data = der;
+ 	*cert_out = cert;
+ 	return SC_SUCCESS;
+ }
+-- 
+1.8.1
+
diff --git a/opensc.spec b/opensc.spec
index 93dafe8..27d443a 100644
--- a/opensc.spec
+++ b/opensc.spec
@@ -1,6 +1,6 @@
 Name:           opensc
 Version:        0.13.0
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:        Smart card library and applications
 
 Group:          System Environment/Libraries
@@ -9,6 +9,9 @@ URL:            https://www.opensc-project.org/
 Source0:        http://downloads.sourceforge.net/project/opensc/OpenSC/opensc-%{version}/%{name}-%{version}.tar.gz
 Source1:        opensc-module
 
+# Upstream patch for fixing pkcs15 cert length calculation
+Patch0:         0001-pkcs15-regression-in-e35febe-compute-cert-length.patch
+
 BuildRequires:  pcsc-lite-devel
 BuildRequires:  readline-devel
 BuildRequires:  openssl-devel
@@ -30,6 +33,7 @@ every software/card that does so, too.
 
 %prep
 %setup -q
+%patch0 -p1 -b .cert_length
 
 sed -i -e 's|"/lib /usr/lib\b|"/%{_lib} %{_libdir}|' configure # lib64 rpaths
 cp -p src/pkcs15init/README ./README.pkcs15init
@@ -114,6 +118,9 @@ rm -f $RPM_BUILD_ROOT%{_libdir}/libopensc.so
 
 
 %changelog
+* Sun Jan 13 2013 Kalev Lember <kalevlember@gmail.com> - 0.13.0-2
+- Backport an upstream patch for fixing pkcs15 cert length calculation
+
 * Thu Jan 03 2013 Milan Broz <mbroz@redhat.com> - 0.13.0-1
 - Update to 0.13.0 (#890770)
 - Remove no longer provided onepin-opensc-pkcs11.so.