diff --git a/opensc-0.20.0-CVE-2023-2977.patch b/opensc-0.20.0-CVE-2023-2977.patch
new file mode 100644
index 0000000..8d3d4fd
--- /dev/null
+++ b/opensc-0.20.0-CVE-2023-2977.patch
@@ -0,0 +1,50 @@
+From 81944d1529202bd28359bede57c0a15deb65ba8a Mon Sep 17 00:00:00 2001
+From: fullwaywang <fullwaywang@tencent.com>
+Date: Mon, 29 May 2023 10:38:48 +0800
+Subject: [PATCH] pkcs15init: correct left length calculation to fix buffer
+ overrun bug. Fixes #2785
+
+---
+ src/pkcs15init/pkcs15-cardos.c | 10 +++++-----
+ 1 file changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/src/pkcs15init/pkcs15-cardos.c b/src/pkcs15init/pkcs15-cardos.c
+index 9715cf390f..f41f73c349 100644
+--- a/src/pkcs15init/pkcs15-cardos.c
++++ b/src/pkcs15init/pkcs15-cardos.c
+@@ -872,7 +872,7 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+ 	sc_apdu_t apdu;
+         u8        rbuf[SC_MAX_APDU_BUFFER_SIZE];
+         int       r;
+-	const u8  *p = rbuf, *q;
++	const u8  *p = rbuf, *q, *pp;
+ 	size_t    len, tlen = 0, ilen = 0;
+ 
+ 	sc_format_apdu(card, &apdu, SC_APDU_CASE_2_SHORT, 0xca, 0x01, 0x88);
+@@ -888,13 +888,13 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+ 		return 0;
+ 
+ 	while (len != 0) {
+-		p = sc_asn1_find_tag(card->ctx, p, len, 0xe1, &tlen);
+-		if (p == NULL)
++		pp = sc_asn1_find_tag(card->ctx, p, len, 0xe1, &tlen);
++		if (pp == NULL)
+ 			return 0;
+ 		if (card->type == SC_CARD_TYPE_CARDOS_M4_3)	{
+ 			/* the verifyRC package on CardOS 4.3B use Manufacturer ID 0x01	*/
+ 			/* and Package Number 0x07					*/
+-			q = sc_asn1_find_tag(card->ctx, p, tlen, 0x01, &ilen);
++			q = sc_asn1_find_tag(card->ctx, pp, tlen, 0x01, &ilen);
+ 			if (q == NULL || ilen != 4)
+ 				return 0;
+ 			if (q[0] == 0x07)
+@@ -902,7 +902,7 @@ static int cardos_have_verifyrc_package(sc_card_t *card)
+ 		} else if (card->type == SC_CARD_TYPE_CARDOS_M4_4)	{
+ 			/* the verifyRC package on CardOS 4.4 use Manufacturer ID 0x03	*/
+ 			/* and Package Number 0x02					*/
+-			q = sc_asn1_find_tag(card->ctx, p, tlen, 0x03, &ilen);
++			q = sc_asn1_find_tag(card->ctx, pp, tlen, 0x03, &ilen);
+ 			if (q == NULL || ilen != 4)
+ 				return 0;
+ 			if (q[0] == 0x02)
+
diff --git a/opensc.spec b/opensc.spec
index 62f25c5..344dc1e 100644
--- a/opensc.spec
+++ b/opensc.spec
@@ -34,6 +34,8 @@ Patch15:        opensc-0.20.0-calloc0.patch
 Patch16:        opensc-0.20.0-file-cache.patch
 # https://github.com/OpenSC/OpenSC/pull/1929
 Patch17:        opensc-0.20.0-idprime.patch
+# https://github.com/OpenSC/OpenSC/pull/2787
+Patch18:        opensc-0.20.0-CVE-2023-2977.patch
 
 
 BuildRequires:  pcsc-lite-devel
@@ -74,6 +76,7 @@ every software/card that does so, too.
 %patch15 -p1 -b .calloc0
 %patch16 -p1 -b .file-cache
 %patch17 -p1 -b .idprime
+%patch18 -p1 -b .CVE-2023-2977
 
 cp -p src/pkcs15init/README ./README.pkcs15init
 cp -p src/scconf/README.scconf .