---
title: cf.tls_client_auth.cert_issuer_dn_rfc2253 · Cloudflare Ruleset Engine docs
description: The Distinguished Name (DN) of the Certificate Authority (CA) that
  issued the certificate in the request in [RFC
  2253](https://datatracker.ietf.org/doc/html/rfc2253) format.
chatbotDeprioritize: false
source_url:
  html: https://developers.cloudflare.com/ruleset-engine/rules-language/fields/reference/cf.tls_client_auth.cert_issuer_dn_rfc2253/
  md: https://developers.cloudflare.com/ruleset-engine/rules-language/fields/reference/cf.tls_client_auth.cert_issuer_dn_rfc2253/index.md
---

# cf.tls\_client\_auth.cert\_issuer\_dn\_rfc2253

`cf.tls_client_auth.cert_issuer_dn_rfc2253` String

The Distinguished Name (DN) of the Certificate Authority (CA) that issued the certificate in the request in [RFC 2253](https://datatracker.ietf.org/doc/html/rfc2253) format.

This field is only filled in if the request includes a client certificate for [mTLS authentication](https://developers.cloudflare.com/ssl/client-certificates/enable-mtls/).

Example value:

```txt
"CN=Access Testing CA,OU=TX,O=Access Testing,L=Austin,ST=Texas,C=US"
```

Categories:

* Request
* mTLS
