diff --git a/mail/altermime/Makefile b/mail/altermime/Makefile
index 7ca9ea029f9..314ae1900ca 100755
--- a/mail/altermime/Makefile
+++ b/mail/altermime/Makefile
@@ -1,9 +1,9 @@
-# $OpenBSD: Makefile,v 1.4 2019/07/14 00:39:38 naddy Exp $
+# $OpenBSD: Makefile,v 1.5 2021/02/10 11:43:58 sthen Exp $
 
 COMMENT=	utility for altering mime-encoded mailpacks
 
 DISTNAME=	altermime-0.3.10
-REVISION=	0
+REVISION=	1
 
 CATEGORIES=	mail
 
@@ -13,6 +13,7 @@ HOMEPAGE=	https://pldaniels.com/altermime/
 # (see share/doc/altermime/LICENCE)
 PERMIT_PACKAGE=	Yes
 
+# uses pledge()
 WANTLIB += c
 
 MASTER_SITES=	${HOMEPAGE}
diff --git a/mail/altermime/patches/patch-altermime_c b/mail/altermime/patches/patch-altermime_c
new file mode 100644
index 00000000000..c7cb9d85894
--- /dev/null
+++ b/mail/altermime/patches/patch-altermime_c
@@ -0,0 +1,26 @@
+$OpenBSD: patch-altermime_c,v 1.1 2021/02/10 11:43:58 sthen Exp $
+
+Index: altermime.c
+--- altermime.c.orig
++++ altermime.c
+@@ -11,6 +11,8 @@ Description:   Altermime is a program/object which wil
+ #include <stdlib.h>
+ #include <string.h>
+ #include <syslog.h>
++#include <unistd.h>
++#include <errno.h>
+ 
+ #include "mime_alter.h"
+ #include "logger.h"
+@@ -319,6 +321,11 @@ int main( int argc, char **argv )
+ 	struct ALTERMIMEAPP_globals glb;
+ 
+ 	LOGGER_set_output_mode(_LOGGER_STDOUT);
++
++	if (pledge("stdio rpath wpath cpath", NULL) == -1) {
++		LOGGER_log("Error: pledge: %s\n", strerror(errno));
++		exit(1);
++	}
+ 
+ 	ALTERMIMEAPP_init( &glb );
+