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Enthusiast

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake after a client alert

Hello,

Has anyone come across this error code before?  I have looked in the 1.1.1 troubleshooting section and there is nothing there. When I click on the link for the description off the error in ISE I get the following error:

Error Code.png

I setup 7925 phones for EAP-TLS using MIC.  I have uploaded Cisco's Root CA and Manufactoring CA Certificates and enabled "Trust for client authentication".  A Certificate Profile is configured matching Common Name and is added to the Identity Sequence.    I got some additional attribute information, where there is a error message:

OpenSSLErrorMessage=SSL alert code=0x233=563 ; source=remote ; type=fatal ; message="decrypt error"

Other Attributes.png

Anyone know what this error means?

20 REPLIES 20
Advocate

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Kyle,

If you are trying to authenticate Cisco phones, can you do me a favor and connect to the phone's https interface (see if you get any errors to see if the cert is corrupt), once you get the certificate warning can you export the phone's certificate using your browser. Once you export the certs you can view the chain and then export the root certificate (if any intermediate certs exist pull them too). You can view the certificate path, double click on the certificate you want to export and the copy to file and that will export the correct certificate.

Then replace the certificates you uploaded and test again.

Tarik Admani
*Please rate helpful posts*

Tarik Admani
*Please rate helpful posts*
Enthusiast

Re: ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshak

The certificates on the phone appear to be in good order.  The Root and Manufacturing root certificates on the phone are identical to the ones installed in ISE.  Could it somehow be failing on the local Self-Signed certificate?

12502  Extracted EAP-Response containing EAP-TLS challenge-response and accepting EAP-TLS as negotiated
12800  Extracted first TLS record; TLS handshake started
12805  Extracted TLS ClientHello message
12806  Prepared TLS ServerHello message
12807  Prepared TLS Certificate message
12809  Prepared TLS CertificateRequest message
12505  Prepared EAP-Request with another EAP-TLS challenge
11006  Returned RADIUS Access-Challenge
11001  Received RADIUS Access-Request
11018  RADIUS is re-using an existing session
12504  Extracted EAP-Response containing EAP-TLS challenge-response
12815  Extracted TLS Alert message
12521  EAP-TLS failed SSL/TLS handshake after a client alert
12507  EAP-TLS authentication failed
11504  Prepared EAP-Failure
11003  Returned RADIUS Access-Reject

      

Advocate

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Yes,

That could be it see if you can follow this guide on importing the ISE self signed cert: (i used a 7921 guide but it should be similar).

http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7921g/7_0/english/administration/guide/7921cfgu.html#wp1376129

Installing the Authentication Server Root Certificate

The Authentication Server Root Certificate must be installed on the Cisco Unified Wireless IP Phone 7921G.

To install the certificate, follow these steps:


Step 1 Export the Authentication Server Root Certificate from the ACS. See Exporting Certificates from the ACS.

Step 2 Go to the phone web page and choose Certificates.

Step 3 Click Import next to the Authentication Server Root certificate.

Step 4 Restart the phone.

Thanks,

Tarik Admani
*Please rate helpful posts*

Tarik Admani
*Please rate helpful posts*
Beginner

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Tarik,

I have exactly the same problem. EAP/TLS failed between 7925G and ISE 1.1.1. I could not solve it with the above propsed solution.

Any other idea?

Enthusiast

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Wim,

I opened a TAC case for this a month and a half ago and I do not have a solution yet.  I was promised an answer by end of this week.  I will post the solution once I have it.

Kyle

Beginner

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Kyle,

Very interesting. Thanks for the info. Looking forward to the result of your case.

best regards,

-wim-

Enthusiast

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Did you ever get a resolution to this? I am about to start working on this exact thing.

Advocate

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

I have seen this issue when you decide not to validate the server side certificate in the phone settings. Seems like it still wants to trust the server side cert anyways.

Tarik Admani
*Please rate helpful posts*

Tarik Admani
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Beginner

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Hi,

i have the same problem. Any updates on this one?

@tarik: please note the 7925 admin guide Table 4-3. "Validate Server Certificate. Note: Applies to PEAP only."

source: http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7925g/7_0/english/administration/guide/7925cfgu.html#wp1361939

So server certificate is always being validated when using EAP-TLS. I think the web gui shouldn't show this option when EAP-TLS is selected.

Anyway, how to solve the problem? Opening of TAC recommended/required?

Cisco Employee

ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshake af

Guys,

There is an enhancement request for phones 7925/7921 to support root cert key length 4096. At this time it only support 2048 so make sure we are not running in the same problem.

CSCtj44859    Request to support 4096 size key certificates

Symptom:

7925 / 7921 not working with 4096 bit keys

Conditions:

CA or cert uploaded on the phone has a 4096 bit key

Workaround:

use 2048 bit key

Jatin Katyal
- Do rate helpful posts -

~Jatin Katyal
Beginner

Re: ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshak

Hi,

thanks for the information.

But all certificates imported to the phone have only 2048 bit keys...

What now?

Enthusiast

Re: ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshak

Sorry I did not get a resolution to this issue.  Customer decided it was not worth the effort and went with a PSK.

Beginner

Re: ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshak

Hi everybody,

what signature algorithm does your ISE certificate (and the chained certificates as well) use?

My certificate in my lab uses sha1. -> no access problem.

A customers's ISE uses sha256. -> problem mentioned above.

Could you please confirm?!

Does the 7925 support sha256?? Even the CiscoRootCA and CiscoManufacturingCA uses sha1...

EDIT:

From 7925 Deployment Guide:

"Only certificates with a key size of 1024 or 2048 are supported.

Ensure the CA server certificate is signed using the SHA-1 algorithm as the SHA-2 (SHA-224, SHA-256, SHA-384, SHA-512)

and SHA-3 signature algorithms are not supported.

Certificates dated January 1 2038 and later are not supported."

source: http://www.cisco.com/en/US/docs/voice_ip_comm/cuipph/7925g/7_0/english/deployment/guide/7925dply.pdf

Cisco Employee

Re: ISE 1.1.1 - Error Code 12521 EAP-TLS failed SSL/TLS handshak

Hi Kianarbabifard,

As per doc, it is supported. From the doc:

If Cisco ISE is set to operate in FIPS mode, the  certificate must be 2048 bits in size and use either SHA-1 or SHA-256  encryption. http://www.cisco.com/en/US/docs/security/ise/1.1/user_guide/ise_man_cert.html#wp1103485

Jatin Katyal
- Do rate helpful posts -

~Jatin Katyal