diff --git a/pkgs/tools/networking/isync/0001-Increase-imap_vprintf-buffer-size.patch b/pkgs/tools/networking/isync/0001-Increase-imap_vprintf-buffer-size.patch
deleted file mode 100644
index 8fefb2d6f73a4..0000000000000
--- a/pkgs/tools/networking/isync/0001-Increase-imap_vprintf-buffer-size.patch
+++ /dev/null
@@ -1,34 +0,0 @@
-From e8a3a20aed135272a9ec0103f4055411c075f043 Mon Sep 17 00:00:00 2001
-From: Michal Sojka <michal.sojka@cvut.cz>
-Date: Mon, 7 Nov 2022 00:07:22 +0100
-Subject: [PATCH] Increase imap_vprintf buffer size
-
-This fixes "Fatal: buffer too small. Please report a bug." error. See
-https://sourceforge.net/p/isync/mailman/isync-devel/thread/87fsevvebj.fsf%40steelpick.2x.cz/#msg37731590
-for related discussion.
-
-When using mbsync with XOAUTH2 authentication (needed for Office365
-mailboxes), the access token used for the LOGIN command may not fit
-into the currently used buffer of 1000 characters. In my case, I need
-the buffer to be at least 2000 characters long. To make this more
-future-proof, I increase the buffer size to 4000 characters.
----
- src/drv_imap.c | 2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
-
-diff --git a/src/drv_imap.c b/src/drv_imap.c
-index c5a7aed..7847192 100644
---- a/src/drv_imap.c
-+++ b/src/drv_imap.c
-@@ -528,7 +528,7 @@ imap_vprintf( const char *fmt, va_list ap )
- 	uint totlen = 0;
- 	const char *segs[MAX_SEGS];
- 	uint segls[MAX_SEGS];
--	char buf[1000];
-+	char buf[4000];
- 
- 	d = buf;
- 	ed = d + sizeof(buf);
--- 
-2.38.1
-
diff --git a/pkgs/tools/networking/isync/default.nix b/pkgs/tools/networking/isync/default.nix
index edf20a6e77c09..b2933ab2e475a 100644
--- a/pkgs/tools/networking/isync/default.nix
+++ b/pkgs/tools/networking/isync/default.nix
@@ -8,20 +8,16 @@
 
 stdenv.mkDerivation rec {
   pname = "isync";
-  version = "1.4.4";
+  version = "1.5.0";
 
   src = fetchurl {
     url = "mirror://sourceforge/isync/${pname}-${version}.tar.gz";
-    sha256 = "1zq0wwvmqsl9y71546dr0aygzn9gjjfiw19hlcq87s929y4p6ckw";
+    sha256 = "oMgeEJOHvyedoWFFMQM5nneUav7PXFH5QTxedzVX940=";
   };
 
-  patches = [
-    # Fixes "Fatal: buffer too small" error
-    ./0001-Increase-imap_vprintf-buffer-size.patch
-    # Fix #202595: SSL error "Socket error: ... unexpected eof while reading"
-    # Source: https://sourceforge.net/p/isync/isync/ci/b6c36624f04cd388873785c0631df3f2f9ac4bf0/
-    ./work-around-unexpected-EOF-error-messages-at-end-of-SSL-connections.patch
-  ];
+
+  # Fixes "Fatal: buffer too small" error
+  env.NIX_CFLAGS_COMPILE = "-DQPRINTF_BUFF=4000";
 
   nativeBuildInputs = [ pkg-config perl ]
     ++ lib.optionals withCyrusSaslXoauth2 [ makeWrapper ];
diff --git a/pkgs/tools/networking/isync/work-around-unexpected-EOF-error-messages-at-end-of-SSL-connections.patch b/pkgs/tools/networking/isync/work-around-unexpected-EOF-error-messages-at-end-of-SSL-connections.patch
deleted file mode 100644
index 9177085ecad77..0000000000000
--- a/pkgs/tools/networking/isync/work-around-unexpected-EOF-error-messages-at-end-of-SSL-connections.patch
+++ /dev/null
@@ -1,76 +0,0 @@
-From b6c36624f04cd388873785c0631df3f2f9ac4bf0 Mon Sep 17 00:00:00 2001
-From: Oswald Buddenhagen <ossi@users.sf.net>
-Date: Mon, 6 Jun 2022 11:55:37 +0200
-Subject: [PATCH] work around "unexpected EOF" error messages at end of SSL
- connections
-
-gmail apparently doesn't send a close notification (SSL_shutdown())
-before closing the TCP socket.
----
- src/drv_imap.c | 7 +++++--
- src/socket.c   | 9 +++++++++
- src/socket.h   | 1 +
- 3 files changed, 15 insertions(+), 2 deletions(-)
-
-diff --git a/src/drv_imap.c b/src/drv_imap.c
-index fb8d165..6286045 100644
---- a/src/drv_imap.c
-+++ b/src/drv_imap.c
-@@ -1620,6 +1620,7 @@ imap_socket_read( void *aux )
- 					error( "IMAP error: unexpected BYE response: %s\n", cmd );
- 					/* We just wait for the server to close the connection now. */
- 					ctx->expectEOF = 1;
-+					socket_expect_eof( &ctx->conn );
- 				} else {
- 					/* We still need to wait for the LOGOUT's tagged OK. */
- 				}
-@@ -1882,10 +1883,12 @@ static void
- imap_cleanup_p2( imap_store_t *ctx,
-                  imap_cmd_t *cmd ATTR_UNUSED, int response )
- {
--	if (response == RESP_NO)
-+	if (response == RESP_NO) {
- 		imap_cancel_store( &ctx->gen );
--	else if (response == RESP_OK)
-+	} else if (response == RESP_OK) {
- 		ctx->expectEOF = 1;
-+		socket_expect_eof( &ctx->conn );
-+	}
- }
- 
- /******************* imap_open_store *******************/
-diff --git a/src/socket.c b/src/socket.c
-index ac3c847..892cece 100644
---- a/src/socket.c
-+++ b/src/socket.c
-@@ -810,6 +810,15 @@ socket_expect_activity( conn_t *conn, int expect )
- 		conf_wakeup( &conn->fd_timeout, expect ? conn->conf->timeout : -1 );
- }
- 
-+void
-+socket_expect_eof( conn_t *sock )
-+{
-+#ifdef SSL_OP_IGNORE_UNEXPECTED_EOF  // implies HAVE_LIBSSL
-+	if (sock->ssl)
-+		SSL_set_options( sock->ssl, SSL_OP_IGNORE_UNEXPECTED_EOF );
-+#endif
-+}
-+
- int
- socket_read( conn_t *conn, char *buf, uint len )
- {
-diff --git a/src/socket.h b/src/socket.h
-index 5b1edd0..af679aa 100644
---- a/src/socket.h
-+++ b/src/socket.h
-@@ -142,6 +142,7 @@ void socket_start_tls(conn_t *conn, void (*cb)( int ok, void *aux ) );
- void socket_start_deflate( conn_t *conn );
- void socket_close( conn_t *sock );
- void socket_expect_activity( conn_t *sock, int expect );
-+void socket_expect_eof( conn_t *sock );
- int socket_read( conn_t *sock, char *buf, uint len ); /* never waits */
- char *socket_read_line( conn_t *sock ); /* don't free return value; never waits */
- typedef enum { KeepOwn = 0, GiveOwn } ownership_t;
--- 
-2.38.0
-