Unable to load Private Key. (PEM routines:PEM_read_bio:no start line:pem_lib.c:648:Expecting: ANY PRIVATE KEY) [closed]

I have a .key file which is PEM formatted private key file. I didn't make this file but I got this from somewhere.

I wanted to see its MD5 hash with openssl tool like below command.

openssl rsa -in server.key -modulus -noout

But this generates below error.

unable to load Private Key
13440:error:0906D06C:PEM routines:PEM_read_bio:no start line:.\crypto\pem\pem_lib.c:648:Expecting: ANY PRIVATE KEY

Here's some asn1parse of the .key file.

openssl asn1parse -in server.key
0:d=0  hl=4 l= 603 cons: SEQUENCE
4:d=1  hl=2 l=   1 prim: INTEGER           :00
7:d=1  hl=3 l= 129 prim: INTEGER           :C141201603899993919CBAA56985E9C7
C6A2AF713A02F5FE88D38CEFBED9304599689280B84B0AB577A9719CA20DDA1246A894AF397A2C57
EE5A582B036CC367E3667454DCD82DBDBF187C35FE39F61C71B517DDDF576F5471B4EC2E045E0F9D
619F5616C4E832F00CBD0DBF41B4BA3CBC4B4B603AE1FE61965917DA732E0DEF
139:d=1  hl=2 l=   3 prim: INTEGER           :010001
144:d=1  hl=3 l= 128 prim: INTEGER           :1687B9AE67562CEDEBDD7A531B84CDB7
093CE138519B93C34B7F626076FF0A262B16EA71904ACB6251A39307C04ADE202055BA13DD9F1539
6123EE408183361A9BC08B9413FA360EA928E48CC3F52B33ACF2980758F02BA2139F652F30A257C2
2E45D7C25835FC4D22B9ECECC12AB632318D4F47E1EBDAD9781B96BCFF03A2D1

 ...

Is there anything more I can try?

Solution 1:

Open the key file in Notepad++ and verify the encoding. If it says UTF-8-BOM then change it to UTF-8. Save the file and try again.

Solution 2:

I changed the header and footer of the PEM file to

-----BEGIN RSA PRIVATE KEY-----

and

-----END RSA PRIVATE KEY-----

Finally, it works!

Solution 3:

Your .key file contains illegal characters. You can check .key file like this:

# file server.key

output "server.key: UTF-8 Unicode (with BOM) text" means it is a plain text, not a key file. The correct output should be "server.key: PEM RSA private key".

Use below command to remove illegal characters:

# tail -c +4 server.key > new_server.key

The new_server.key should be correct.

For more detail, you can click here

Solution 4:

Create CA certificate

openssl genrsa -out privateKey.pem 4096
openssl req -new -x509 -nodes -days 3600 -key privateKey.pem -out caKey.pem

Solution 5:

> I have a .key file which is PEM formatted private key file.
> ...
> Here's some asn1parse of the .key file...

That it appears OK with asn1parse leads me to believe its not PEM encoded.

Is there anything more I can try?

Because it appears to be ASN.1, try:

$ openssl rsa -in server.key -inform DER -modulus -noout

Notice the -inform DER to switch between encodings.