Duplicate headers received from server - google-chrome

Question

Duplicate headers received from server
The response from the server contained duplicate headers. This problem is generally the result of a misconfigured website or proxy. Only the website or proxy administrator can fix this issue.
Error 349 (net::ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_DISPOSITION): Multiple distinct Content-Disposition headers received. This is disallowed to protect against HTTP response splitting attacks.
I found this error while exporting to pdf in chrome.
Response.Buffer = false;
Response.ClearHeaders();
string ext = objProp.PACKAGEFILENAME.Substring(objProp.PACKAGEFILENAME.LastIndexOf("."));
string ext1 = ext.Substring(1);
Response.ContentType = ext1;
Response.AddHeader("Content-Disposition", "target;_blank,attachment; filename=" + objProp.PACKAGEFILENAME);
const int ChunkSize = 1024;
byte[] binary = objProp.PACKAGEDOCUMENT;
System.IO.MemoryStream ms = new System.IO.MemoryStream(binary);
int SizeToWrite = ChunkSize;
for (int i = 0; i < binary.GetUpperBound(0) - 1; i = i + ChunkSize)
{
if (!Response.IsClientConnected) return;
if (i + ChunkSize >= binary.Length) SizeToWrite = binary.Length - i;
byte[] chunk = new byte[SizeToWrite];
ms.Read(chunk, 0, SizeToWrite);
Response.BinaryWrite(chunk);
Response.Flush();
}
Response.Close();
How to fix this?

Answer 1

This ones a little old but was high in the google ranking so I thought I would throw in the answer I found from Chrome, pdf display, Duplicate headers received from the server
Basically my problem also was that the filename contained commas. Do a replace on commas to remove them and you should be fine. My function to make a valid filename is below.
public static string MakeValidFileName(string name)
{
string invalidChars = Regex.Escape(new string(System.IO.Path.GetInvalidFileNameChars()));
string invalidReStr = string.Format(#"[{0}]+", invalidChars);
string replace = Regex.Replace(name, invalidReStr, "_").Replace(";", "").Replace(",", "");
return replace;
}

Answer 2

The server SHOULD put double quotes around the filename, as mentioned by #cusman and #Touko in their replies.
For example:
Response.AddHeader("Content-Disposition", "attachment;filename=\"" + filename + "\"");

Answer 3

Just put a pair of double quotes around your file name like this:
this.Response.AddHeader("Content-disposition", $"attachment; filename=\"{outputFileName}\"");

Answer 4

For me the issue was about a comma not in the filename but as below: -
Response.ok(streamingOutput,MediaType.APPLICATION_OCTET_STREAM_TYPE).header("content-disposition", "attachment, filename=your_file_name").build();
I accidentally put a comma after attachment. Got it resolved by replacing comma with a semicolon.

Answer 5

Double quotes around the filename in the header is the standard per MDN web docs. Omitting the quotes creates multiple opportunities for problems arising from characters in the filename.

Answer 6

I've got this same error (ERR_RESPONSE_HEADERS_MULTIPLE_CONTENT_DISPOSITION) downloading from EDGE a dynamic filename named
"a,b,c test.zip"
The problem was the comma.
Strangely, using the old "internet explorer", the comma was not a problem and the same file was downloaded (same procedure same file). Using other browser the error occured.
WORKAROUND: normalize filename (by code) replacing any comma into underscore, if evolved browsers are used.