diff -Nru gnutls28-3.8.9/debian/changelog gnutls28-3.8.9/debian/changelog
--- gnutls28-3.8.9/debian/changelog	2025-07-09 12:34:38.000000000 +0200
+++ gnutls28-3.8.9/debian/changelog	2025-11-23 14:13:38.000000000 +0100
@@ -1,3 +1,10 @@
+gnutls28 (3.8.9-3+deb13u1) trixie; urgency=medium
+
+  * Add patch for CVE-2025-9820 / GNUTLS-SA-2025-11-18 from 3.8.11.
+    Closes: #1121146
+
+ -- Andreas Metzler <ametzler@debian.org>  Sun, 23 Nov 2025 14:13:38 +0100
+
 gnutls28 (3.8.9-3) unstable; urgency=medium
 
   * Cherry-pick fixes from 3.8.10 release:
diff -Nru gnutls28-3.8.9/debian/patches/48_0001-pkcs11-avoid-stack-overwrite-when-initializing-a-tok.patch gnutls28-3.8.9/debian/patches/48_0001-pkcs11-avoid-stack-overwrite-when-initializing-a-tok.patch
--- gnutls28-3.8.9/debian/patches/48_0001-pkcs11-avoid-stack-overwrite-when-initializing-a-tok.patch	1970-01-01 01:00:00.000000000 +0100
+++ gnutls28-3.8.9/debian/patches/48_0001-pkcs11-avoid-stack-overwrite-when-initializing-a-tok.patch	2025-11-23 14:13:38.000000000 +0100
@@ -0,0 +1,261 @@
+From 1d56f96f6ab5034d677136b9d50b5a75dff0faf5 Mon Sep 17 00:00:00 2001
+From: Daiki Ueno <ueno@gnu.org>
+Date: Tue, 18 Nov 2025 13:17:55 +0900
+Subject: [PATCH] pkcs11: avoid stack overwrite when initializing a token
+
+If gnutls_pkcs11_token_init is called with label longer than 32
+characters, the internal storage used to blank-fill it would
+overflow. This adds a guard to prevent that.
+
+Signed-off-by: Daiki Ueno <ueno@gnu.org>
+---
+ .gitignore                |   2 +
+ NEWS                      |   4 +
+ lib/pkcs11_write.c        |   5 +-
+ tests/Makefile.am         |   2 +-
+ tests/pkcs11/long-label.c | 164 ++++++++++++++++++++++++++++++++++++++
+ 5 files changed, 174 insertions(+), 3 deletions(-)
+ create mode 100644 tests/pkcs11/long-label.c
+
+--- a/NEWS
++++ b/NEWS
+@@ -3,10 +3,16 @@ Bug numbers referenced in this log corre
+ available at https://gitlab.com/gnutls/gnutls/issues
+ Copyright (C) 2000-2016 Free Software Foundation, Inc.
+ Copyright (C) 2013-2019 Nikos Mavrogiannopoulos
+ See the end for copying conditions.
+ 
++* Version 3.8.11
++
++** libgnutls: Fix stack overwrite in gnutls_pkcs11_token_init
++   Reported by Luigino Camastra from Aisle Research. [GNUTLS-SA-2025-11-18,
++   CVSS: low] [CVE-2025-9820]
++
+ * Version 3.8.10
+ 
+ ** libgnutls: Fix NULL pointer dereference when 2nd Client Hello omits PSK
+    Reported by Stefan Bühler. [GNUTLS-SA-2025-07-07-4, CVSS: medium]
+    [CVE-2025-6395]
+--- a/lib/pkcs11_write.c
++++ b/lib/pkcs11_write.c
+@@ -26,10 +26,11 @@
+ #include "datum.h"
+ #include "pkcs11_int.h"
+ #include "pkcs11x.h"
+ #include "x509/common.h"
+ #include "pk.h"
++#include "minmax.h"
+ 
+ static const ck_bool_t tval = 1;
+ static const ck_bool_t fval = 0;
+ 
+ #define MAX_ASIZE 24
+@@ -1170,11 +1171,11 @@ int gnutls_pkcs11_delete_url(const char
+ 
+ /**
+  * gnutls_pkcs11_token_init:
+  * @token_url: A PKCS #11 URL specifying a token
+  * @so_pin: Security Officer's PIN
+- * @label: A name to be used for the token
++ * @label: A name to be used for the token, at most 32 characters
+  *
+  * This function will initialize (format) a token. If the token is
+  * at a factory defaults state the security officer's PIN given will be
+  * set to be the default. Otherwise it should match the officer's PIN.
+  *
+@@ -1208,11 +1209,11 @@ int gnutls_pkcs11_token_init(const char
+ 	}
+ 
+ 	/* so it seems memset has other uses than zeroing! */
+ 	memset(flabel, ' ', sizeof(flabel));
+ 	if (label != NULL)
+-		memcpy(flabel, label, strlen(label));
++		memcpy(flabel, label, MIN(sizeof(flabel), strlen(label)));
+ 
+ 	rv = pkcs11_init_token(module, slot, (uint8_t *)so_pin, strlen(so_pin),
+ 			       (uint8_t *)flabel);
+ 	if (rv != CKR_OK) {
+ 		gnutls_assert();
+--- a/tests/Makefile.am
++++ b/tests/Makefile.am
+@@ -501,11 +501,12 @@ pathbuf_CPPFLAGS = $(AM_CPPFLAGS) \
+ 	-I$(top_builddir)/gl
+ 
+ if ENABLE_PKCS11
+ if !WINDOWS
+ ctests += tls13/post-handshake-with-cert-pkcs11 pkcs11/tls-neg-pkcs11-no-key \
+-	global-init-override pkcs11/distrust-after
++	global-init-override pkcs11/distrust-after \
++	pkcs11/long-label
+ tls13_post_handshake_with_cert_pkcs11_DEPENDENCIES = libpkcs11mock2.la libutils.la
+ tls13_post_handshake_with_cert_pkcs11_LDADD = $(LDADD) $(LIBDL)
+ pkcs11_tls_neg_pkcs11_no_key_DEPENDENCIES = libpkcs11mock2.la libutils.la
+ pkcs11_tls_neg_pkcs11_no_key_LDADD = $(LDADD) $(LIBDL)
+ pkcs11_distrust_after_DEPENDENCIES = libpkcs11mock3.la libutils.la
+--- /dev/null
++++ b/tests/pkcs11/long-label.c
+@@ -0,0 +1,164 @@
++/*
++ * Copyright (C) 2025 Red Hat, Inc.
++ *
++ * Author: Daiki Ueno
++ *
++ * This file is part of GnuTLS.
++ *
++ * GnuTLS is free software; you can redistribute it and/or modify it
++ * under the terms of the GNU General Public License as published by
++ * the Free Software Foundation; either version 3 of the License, or
++ * (at your option) any later version.
++ *
++ * GnuTLS is distributed in the hope that it will be useful, but
++ * WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
++ * General Public License for more details.
++ *
++ * You should have received a copy of the GNU Lesser General Public License
++ * along with this program.  If not, see <https://www.gnu.org/licenses/>
++ */
++
++#ifdef HAVE_CONFIG_H
++#include "config.h"
++#endif
++
++#include <stdbool.h>
++#include <stdio.h>
++#include <stdlib.h>
++
++#if defined(_WIN32)
++
++int main(void)
++{
++	exit(77);
++}
++
++#else
++
++#include <string.h>
++#include <unistd.h>
++#include <gnutls/gnutls.h>
++
++#include "cert-common.h"
++#include "pkcs11/softhsm.h"
++#include "utils.h"
++
++/* This program tests that a token can be initialized with
++ * a label longer than 32 characters.
++ */
++
++static void tls_log_func(int level, const char *str)
++{
++	fprintf(stderr, "server|<%d>| %s", level, str);
++}
++
++#define PIN "1234"
++
++#define CONFIG_NAME "softhsm-long-label"
++#define CONFIG CONFIG_NAME ".config"
++
++static int pin_func(void *userdata, int attempt, const char *url,
++		    const char *label, unsigned flags, char *pin,
++		    size_t pin_max)
++{
++	if (attempt == 0) {
++		strcpy(pin, PIN);
++		return 0;
++	}
++	return -1;
++}
++
++static void test(const char *provider)
++{
++	int ret;
++	size_t i;
++
++	gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
++
++	success("test with %s\n", provider);
++
++	if (debug) {
++		gnutls_global_set_log_function(tls_log_func);
++		gnutls_global_set_log_level(4711);
++	}
++
++	/* point to SoftHSM token that libpkcs11mock4.so internally uses */
++	setenv(SOFTHSM_ENV, CONFIG, 1);
++
++	gnutls_pkcs11_set_pin_function(pin_func, NULL);
++
++	ret = gnutls_pkcs11_add_provider(provider, "trusted");
++	if (ret != 0) {
++		fail("gnutls_pkcs11_add_provider: %s\n", gnutls_strerror(ret));
++	}
++
++	/* initialize softhsm token */
++	ret = gnutls_pkcs11_token_init(
++		SOFTHSM_URL, PIN,
++		"this is a very long label whose length exceeds 32");
++	if (ret < 0) {
++		fail("gnutls_pkcs11_token_init: %s\n", gnutls_strerror(ret));
++	}
++
++	for (i = 0;; i++) {
++		char *url = NULL;
++
++		ret = gnutls_pkcs11_token_get_url(i, 0, &url);
++		if (ret < 0)
++			break;
++		if (strstr(url,
++			   "token=this%20is%20a%20very%20long%20label%20whose"))
++			break;
++	}
++	if (ret < 0)
++		fail("gnutls_pkcs11_token_get_url: %s\n", gnutls_strerror(ret));
++
++	gnutls_pkcs11_deinit();
++}
++
++void doit(void)
++{
++	const char *bin;
++	const char *lib;
++	char buf[128];
++
++	if (gnutls_fips140_mode_enabled())
++		exit(77);
++
++	/* this must be called once in the program */
++	global_init();
++
++	/* we call gnutls_pkcs11_init manually */
++	gnutls_pkcs11_deinit();
++
++	/* check if softhsm module is loadable */
++	lib = softhsm_lib();
++
++	/* initialize SoftHSM token that libpkcs11mock4.so internally uses */
++	bin = softhsm_bin();
++
++	set_softhsm_conf(CONFIG);
++	snprintf(buf, sizeof(buf),
++		 "%s --init-token --slot 0 --label test --so-pin " PIN
++		 " --pin " PIN,
++		 bin);
++	system(buf);
++
++	test(lib);
++
++	lib = getenv("P11MOCKLIB4");
++	if (lib == NULL) {
++		fail("P11MOCKLIB4 is not set\n");
++	}
++
++	set_softhsm_conf(CONFIG);
++	snprintf(buf, sizeof(buf),
++		 "%s --init-token --slot 0 --label test --so-pin " PIN
++		 " --pin " PIN,
++		 bin);
++	system(buf);
++
++	test(lib);
++}
++#endif /* _WIN32 */
diff -Nru gnutls28-3.8.9/debian/patches/series gnutls28-3.8.9/debian/patches/series
--- gnutls28-3.8.9/debian/patches/series	2025-07-09 11:40:47.000000000 +0200
+++ gnutls28-3.8.9/debian/patches/series	2025-11-23 14:13:38.000000000 +0100
@@ -9,3 +9,4 @@
 47_0004-x509-avoid-double-free-when-exporting-othernames-in-.patch
 47_0005-certtool-avoid-1-byte-write-buffer-overrun-when-pars.patch
 47_0006-handshake-clear-HSK_PSK_SELECTED-is-when-resetting-b.patch
+48_0001-pkcs11-avoid-stack-overwrite-when-initializing-a-tok.patch
