diff --git a/doc/Changelog b/doc/Changelog
index 9c1f80762..56e8d4dcd 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -4,6 +4,10 @@
 	  Failed loads clear the zone data, so there is no partial
 	  zone. Thanks to Qifan Zhang, Palo Alto Networks, for
 	  the report.
+	- Fix that when SVCB records cannot be written out, and
+	  are written in unknown format, that the zone read allows
+	  such unknown format SVCB records. Thanks to Qifan Zhang,
+	  Palo Alto Networks, for the report.
 
 15 June 2026: Wouter
 	- Fix to add `max-transfer-size` and `max-transfer-time` that
diff --git a/sldns/str2wire.c b/sldns/str2wire.c
index 50a71d397..d2c44980c 100644
--- a/sldns/str2wire.c
+++ b/sldns/str2wire.c
@@ -842,7 +842,8 @@ rrinternal_parse_rdata(sldns_buffer* strbuf, char* token, size_t token_len,
 	sldns_write_uint16(rr+dname_len+8, (uint16_t)(rr_cur_len-dname_len-10));
 	*rr_len = rr_cur_len;
 	/* SVCB/HTTPS handling  */
-	if (rr_type == LDNS_RR_TYPE_SVCB || rr_type == LDNS_RR_TYPE_HTTPS) {
+	if ((rr_type == LDNS_RR_TYPE_SVCB || rr_type == LDNS_RR_TYPE_HTTPS)
+		&& !was_unknown_rr_format) {
 		size_t rdata_len = rr_cur_len - dname_len - 10;
 		uint8_t *rdata = rr+dname_len + 10;