untrusted comment: verify with openbsd-77-base.pub
RWSbCCUoGpcxVc8P+mOAqUkIPn3WE8z2sagGnReVAapPmA3/S314qOed4L6fZc94I8iNgiWEF4t0ntG9aJIoP6GFU/2aJdU+SgM=

OpenBSD 7.7 errata 039, April 21, 2026:

slaacd(8) could crash due to buffer overflow.

Apply by doing:
    signify -Vep /etc/signify/openbsd-77-base.pub -x 039_slaacd.patch.sig \
        -m - | (cd /usr/src && patch -p0)

And then rebuild and install slaacd:
    cd /usr/src/sbin/slaacd
    make obj
    make
    make install

Index: sbin/slaacd/engine.c
===================================================================
RCS file: /cvs/src/sbin/slaacd/engine.c,v
diff -u -p -r1.99.4.1 engine.c
--- sbin/slaacd/engine.c	13 Apr 2026 15:50:39 -0000	1.99.4.1
+++ sbin/slaacd/engine.c	17 Apr 2026 11:12:14 -0000
@@ -2085,7 +2085,7 @@ update_iface_ra_rdns(struct slaacd_iface
 	LIST_FOREACH(radv_rdns, &ra->rdns_servers, entries) {
 		memcpy(&rdns[rdns_count++],
 		    &radv_rdns->rdns, sizeof(struct in6_addr));
-		if (rdns_proposal->rdns_count == MAX_RDNS_COUNT)
+		if (rdns_count == MAX_RDNS_COUNT)
 			break;
 	}