diff -Nru a/modules/filters/mod_deflate.c b/modules/filters/mod_deflate.c
--- a/modules/filters/mod_deflate.c	2018-10-10 17:40:35.000000000 +0200
+++ b/modules/filters/mod_deflate.c	2019-03-16 16:24:50.126848429 +0100
@@ -533,6 +533,7 @@
     apr_size_t len = 0, blen;
     const char *data;
     deflate_filter_config *c;
+    apr_status_t rv;
 
     /* Do nothing if asked to filter nothing. */
     if (APR_BRIGADE_EMPTY(bb)) {
@@ -930,14 +931,18 @@
         }
 
         /* read */
-        apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
-        if (!len) {
+        rv = apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+        if (rv != APR_SUCCESS || !len) {
             apr_bucket_delete(e);
             continue;
         }
         if (len > APR_INT32_MAX) {
             apr_bucket_split(e, APR_INT32_MAX);
-            apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+            rv = apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+            if (rv != APR_SUCCESS) {
+                apr_bucket_delete(e);
+                continue;
+            }
         }
 
         /* This crc32 function is from zlib. */
@@ -1315,13 +1320,16 @@
             }
 
             /* read */
-            apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ);
-            if (!len) {
+            rv = apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ);
+            if (rv != APR_SUCCESS || !len) {
                 continue;
             }
             if (len > APR_INT32_MAX) {
                 apr_bucket_split(bkt, APR_INT32_MAX);
-                apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ);
+                rv = apr_bucket_read(bkt, &data, &len, APR_BLOCK_READ);
+                if (rv != APR_SUCCESS) {
+                    continue;
+                }
             }
 
             if (ctx->zlib_flags) {
@@ -1703,14 +1711,18 @@
         }
 
         /* read */
-        apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
-        if (!len) {
+        rv = apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+        if (rv != APR_SUCCESS || !len) {
             apr_bucket_delete(e);
             continue;
         }
         if (len > APR_INT32_MAX) {
             apr_bucket_split(e, APR_INT32_MAX);
-            apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+            rv = apr_bucket_read(e, &data, &len, APR_BLOCK_READ);
+            if (rv != APR_SUCCESS) {
+                apr_bucket_delete(e);
+                continue;
+            }
         }
 
         /* first bucket contains zlib header */