diff --git a/doc/Changelog b/doc/Changelog
index f92de7fd0..5981ac2fa 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,10 @@
+24 March 2026: Wouter
+	- Fix to check for invalid http content length and chunk size,
+	  and to check the RR rdata field lengths when decompressing and
+	  inserting RRs from an authority zone transfer. This stops
+	  large memory use and heap buffer-overflow read errors. Thanks
+	  to Haruto Kimura (Stella) for the report.
+
 20 March 2026: Wouter
 	- Fix for testcode pktview to check buffer size and log errors.
 
diff --git a/services/authzone.c b/services/authzone.c
index 3965b5e17..9778cf1b7 100644
--- a/services/authzone.c
+++ b/services/authzone.c
@@ -1384,6 +1384,9 @@ decompress_rr_into_buffer(struct sldns_buffer* buf, uint8_t* pkt,
 				len = 0;
 				break;
 			case LDNS_RDF_TYPE_STR:
+				/* Check rdlen for resilience, because it is
+				 * checked above, that rdlen > 0 */
+				if(rdlen < 1) return 0; /* malformed */
 				len = rd[0] + 1;
 				break;
 			default:
@@ -1391,6 +1394,8 @@ decompress_rr_into_buffer(struct sldns_buffer* buf, uint8_t* pkt,
 				break;
 			}
 			if(len) {
+				if(len > rdlen)
+					return 0; /* malformed */
 				if(!sldns_buffer_available(buf, len))
 					return 0; /* too long for buffer */
 				sldns_buffer_write(buf, rd, len);
diff --git a/util/netevent.c b/util/netevent.c
index 01ef54dfe..a86e22518 100644
--- a/util/netevent.c
+++ b/util/netevent.c
@@ -4870,8 +4870,17 @@ http_process_initial_header(struct comm_point* c)
 			return 0;
 		}
 	} else if(strncasecmp(line, "Content-Length: ", 16) == 0) {
-		if(!c->http_is_chunked)
-			c->tcp_byte_count = (size_t)atoi(line+16);
+		if(!c->http_is_chunked) {
+			char* end = NULL;
+			long long cl;
+			errno = 0;
+			cl = strtoll(line+16, &end, 10);
+			if(end == line+16 || errno != 0 || cl < 0) {
+				verbose(VERB_ALGO, "http invalid Content-Length: " ARG_LL "d", cl);
+				return 0; /* reject */
+			}
+			c->tcp_byte_count = (size_t)cl;
+		}
 	} else if(strncasecmp(line, "Transfer-Encoding: chunked", 19+7) == 0) {
 		c->tcp_byte_count = 0;
 		c->http_is_chunked = 1;
@@ -4927,9 +4936,15 @@ http_process_chunk_header(struct comm_point* c)
 	if(c->http_in_chunk_headers == 1) {
 		/* read chunked start line */
 		char* end = NULL;
-		c->tcp_byte_count = (size_t)strtol(line, &end, 16);
-		if(end == line)
+		long chunk_sz;
+		errno = 0;
+		chunk_sz = strtol(line, &end, 16);
+		if(end == line || errno != 0 || chunk_sz < 0) {
+			verbose(VERB_ALGO, "http invalid chunk size: %ld",
+				chunk_sz);
 			return 0;
+		}
+		c->tcp_byte_count = (size_t)chunk_sz;
 		c->http_in_chunk_headers = 0;
 		/* remove header text from front of buffer */
 		http_moveover_buffer(c->buffer);