untrusted comment: verify with openbsd-68-base.pub
RWQZj25CSG5R2gnNBM/MLVkbtgEwuNc4kBgrQXFm/4TY0Xb/OwkZ3f38s/We42C6FF/E+g7/FI0axlpGqM7VZinkmHMbxgodago=

OpenBSD 6.8 errata 028, August 11, 2021:

In a specific configuration, wg(4) leaked mbufs.

Apply by doing:
   signify -Vep /etc/signify/openbsd-68-base.pub -x 028_wg.patch.sig \
       -m - | (cd /usr/src && patch -p0)

And then rebuild and install a new kernel:
   KK=`sysctl -n kern.osversion | cut -d# -f1`
   cd /usr/src/sys/arch/`machine`/compile/$KK
   make obj
   make config
   make
   make install

Index: sys/net/if_wg.c
===================================================================
RCS file: /cvs/src/sys/net/if_wg.c,v
diff -u -p -u -r1.14 if_wg.c
--- sys/net/if_wg.c     1 Sep 2020 19:06:59 -0000       1.14
+++ sys/net/if_wg.c     5 Aug 2021 14:06:30 -0000
@@ -810,6 +810,7 @@ wg_send(struct wg_softc *sc, struct wg_e
                           IPPROTO_IPV6);
#endif
       } else {
+               m_freem(m);
               return EAFNOSUPPORT;
       }