diff --git a/backend/s3/s3.go b/backend/s3/s3.go
index 1bed705dc..fefdd6e96 100644
--- a/backend/s3/s3.go
+++ b/backend/s3/s3.go
@@ -4458,7 +4458,7 @@ func (f *Fs) list(ctx context.Context, opt listOpt, fn listFn) error {
 		}
 		foundItems += len(resp.Contents)
 		for i, object := range resp.Contents {
-			remote := deref(object.Key)
+			remote := *stringClone(deref(object.Key))
 			if urlEncodeListings {
 				remote, err = url.QueryUnescape(remote)
 				if err != nil {
@@ -5911,7 +5911,7 @@ func (o *Object) readMetaData(ctx context.Context) (err error) {
 func s3MetadataToMap(s3Meta map[string]string) map[string]string {
 	meta := make(map[string]string, len(s3Meta))
 	for k, v := range s3Meta {
-		meta[strings.ToLower(k)] = v
+		meta[strings.ToLower(k)] = *stringClone(v)
 	}
 	return meta
 }
@@ -5954,14 +5954,14 @@ func (o *Object) setMetaData(resp *s3.HeadObjectOutput) {
 			o.lastModified = *resp.LastModified
 		}
 	}
-	o.mimeType = deref(resp.ContentType)
+	o.mimeType = strings.Clone(deref(resp.ContentType))
 
 	// Set system metadata
-	o.storageClass = (*string)(&resp.StorageClass)
-	o.cacheControl = resp.CacheControl
-	o.contentDisposition = resp.ContentDisposition
-	o.contentEncoding = resp.ContentEncoding
-	o.contentLanguage = resp.ContentLanguage
+	o.storageClass = stringClone(string(resp.StorageClass))
+	o.cacheControl = stringClonePointer(resp.CacheControl)
+	o.contentDisposition = stringClonePointer(resp.ContentDisposition)
+	o.contentEncoding = stringClonePointer(resp.ContentEncoding)
+	o.contentLanguage = stringClonePointer(resp.ContentLanguage)
 
 	// If decompressing then size and md5sum are unknown
 	if o.fs.opt.Decompress && deref(o.contentEncoding) == "gzip" {
@@ -6476,8 +6476,8 @@ func (o *Object) uploadMultipart(ctx context.Context, src fs.ObjectInfo, in io.R
 	}
 
 	var s3cw *s3ChunkWriter = chunkWriter.(*s3ChunkWriter)
-	gotETag = s3cw.eTag
-	versionID = aws.String(s3cw.versionID)
+	gotETag = *stringClone(s3cw.eTag)
+	versionID = stringClone(s3cw.versionID)
 
 	hashOfHashes := md5.Sum(s3cw.md5s)
 	wantETag = fmt.Sprintf("%s-%d", hex.EncodeToString(hashOfHashes[:]), len(s3cw.completedParts))
@@ -6509,8 +6509,8 @@ func (o *Object) uploadSinglepartPutObject(ctx context.Context, req *s3.PutObjec
 	}
 	lastModified = time.Now()
 	if resp != nil {
-		etag = deref(resp.ETag)
-		versionID = resp.VersionId
+		etag = *stringClone(deref(resp.ETag))
+		versionID = stringClonePointer(resp.VersionId)
 	}
 	return etag, lastModified, versionID, nil
 }
@@ -6562,8 +6562,8 @@ func (o *Object) uploadSinglepartPresignedRequest(ctx context.Context, req *s3.P
 		if date, err := http.ParseTime(resp.Header.Get("Date")); err != nil {
 			lastModified = date
 		}
-		etag = resp.Header.Get("Etag")
-		vID := resp.Header.Get("x-amz-version-id")
+		etag = *stringClone(resp.Header.Get("Etag"))
+		vID := *stringClone(resp.Header.Get("x-amz-version-id"))
 		if vID != "" {
 			versionID = &vID
 		}