diff --git a/debian/patches/28_check_snmp_fix_regex_matches b/debian/patches/28_check_snmp_fix_regex_matches
new file mode 100644
index 0000000..c3e8708
--- /dev/null
+++ b/debian/patches/28_check_snmp_fix_regex_matches
@@ -0,0 +1,78 @@
+From 12d1b0cbab5469e230ea5b69b5f1fc411836de21 Mon Sep 17 00:00:00 2001
+From: Sven Nierlein <sven@nierlein.de>
+Date: Thu, 19 Jan 2023 23:29:01 +0100
+Subject: [PATCH] fix check_snmp regex matches
+
+the multiplier function always tried to extract a number, even if the result
+is a string because of using a mib.
+
+before:
+```
+./check_snmp -H hostname -P2c -c public -o IF-MIB::ifAdminStatus.11466 -vvv -r 0
+/usr/bin/snmpget -Le -t 10 -r 5 -m ALL -v 2c [context] [authpriv] 10.0.13.11:161 IF-MIB::ifAdminStatus.11466
+IF-MIB::ifAdminStatus.11466 = INTEGER: up(1)
+Processing oid 1 (line 1)
+  oidname: IF-MIB::ifAdminStatus.11466
+  response:  = INTEGER: up(1)
+SNMP OK - 0 | IF-MIB::ifAdminStatus.11466=0;;
+```
+
+the regexp 0 matches, even if the actual result is "up(1)".
+
+after this patch:
+```
+./check_snmp -H hostname -P2c -c public -o IF-MIB::ifAdminStatus.11466 -vvv -r 0
+/usr/bin/snmpget -Le -t 10 -r 5 -m ALL -v 2c [context] [authpriv] 10.0.13.11:161 IF-MIB::ifAdminStatus.11466
+IF-MIB::ifAdminStatus.11466 = INTEGER: up(1)
+Processing oid 1 (line 1)
+  oidname: IF-MIB::ifAdminStatus.11466
+  response:  = INTEGER: up(1)
+SNMP CRITICAL - *up(1)* |
+```
+---
+ plugins/check_snmp.c | 23 +++++++++++++++++++++--
+ 1 file changed, 21 insertions(+), 2 deletions(-)
+
+diff --git a/plugins/check_snmp.c b/plugins/check_snmp.c
+index 56bad8800..d3968a27d 100644
+--- a/plugins/check_snmp.c
++++ b/plugins/check_snmp.c
+@@ -1165,17 +1165,36 @@ nextarg (char *str)
+ char *
+ multiply (char *str)
+ {
+-	double val = strtod (str, NULL);
+-	val *= multiplier;
++	char *endptr;
++	double val;
+ 	char *conv = "%f";
++
++	if(verbose>2)
++		printf("    multiply input: %s\n", str);
++
++	val = strtod (str, &endptr);
++	if ((val == 0.0) && (endptr == str)) {
++		if(multiplier != 1) {
++			die(STATE_UNKNOWN, _("multiplier set (%.1f), but input is not a number: %s"), multiplier, str);
++		}
++		return str;
++	}
++
++	if(verbose>2)
++		printf("    multiply extracted double: %f\n", val);
++	val *= multiplier;
+ 	if (fmtstr != "") {
+ 		conv = fmtstr;
+ 	}
+ 	if (val == (int)val) {
+ 		sprintf(str, "%.0f", val);
+ 	} else {
++		if(verbose>2)
++			printf("    multiply using format: %s\n", conv);
+ 		sprintf(str, conv, val);
+ 	}
++	if(verbose>2)
++		printf("    multiply result: %s\n", str);
+ 	return str;
+ }
+ 
diff --git a/debian/patches/series b/debian/patches/series
index ff1beff..8730b6b 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -16,3 +16,4 @@
 25_spell_fixes
 26_check_mailq_fix_nullmailer_regex
 27_check_snmp_add_multiplier
+28_check_snmp_fix_regex_matches