diff --git a/s3api/utils/signed-chunk-reader.go b/s3api/utils/signed-chunk-reader.go
index 2b2c6c36..4ece3607 100644
--- a/s3api/utils/signed-chunk-reader.go
+++ b/s3api/utils/signed-chunk-reader.go
@@ -230,11 +230,14 @@ const (
 	maxHeaderSize = 1024
 )
 
-// Theis returns the chunk payload size, signature, data start offset, and
+// This returns the chunk payload size, signature, data start offset, and
 // error if any. See the AWS documentation for the chunk header format. The
 // header[0] byte is expected to be the first byte of the chunk size here.
 func (cr *ChunkReader) parseChunkHeaderBytes(header []byte) (int64, string, int, error) {
 	stashLen := len(cr.stash)
+	if stashLen > maxHeaderSize {
+		return 0, "", 0, errInvalidChunkFormat
+	}
 	if cr.stash != nil {
 		tmp := make([]byte, maxHeaderSize)
 		copy(tmp, cr.stash)