TLS1.0 support - nginx:1.25.3, all versions

[Chokoabigail]

Describe the bug

The latest version of nginx (nginx:1.25.3, from all versions) does not support TLS1.0.

To reproduce

Deploy nginx:1.25.3 and set nginx ssl_protocols to TLSv1 TLSv1.1 TLSv1.2 TLSv1.3, you can put in the ssl_ciphers what ever value you want0

Expected behavior

Working TLS1.0 - can be tested using OpenSSL client.

Your environment

My OS is Ubuntu 22, when I used a different nginx flavor image (Openresty the latest version) on the same OS, TLS 1 worked without any issue, so from this, I learned that this is not an OS issue, this is about the nginx docker itself.

Additional context

After searching online, I found a few recommended solutions:

A.Edit /etc/ssl/openssl.cnf and add to it:

[openssl_init]
 providers = provider_sect
+ssl_conf = ssl_sect
+
+[ssl_sect]
+system_default = system_default_sect
+
+[system_default_sect]
+CipherString = DEFAULT@SECLEVEL=0

B. add this ssl_ciphers DEFAULT@SECLEVEL=0; to the nginx conf.

I tried both of the methods, I edited /etc/ssl/openssl.cnf inside and outside the docker, and I tried the B option, but none of that worked, I read in another post that the Alpine version didn't compile in the TLS1.0 support so I switched from the alpine version to the regular nginx:1.25.3 and still nothing worked (including after I tried the above in it and outside it).

How can I make it work? is there a specific version of the regular Nginx that works with this? Do I need to do something differently to make it work? I must support TLS1.0 as well...

[Chokoabigail]

Ideally looking for a version that supports both TLS1.0 and http2

[thresheek]

Hi @Chokoabigail!

TLS 1.0 and http2 seem to work fine with nginx:1.25.3 which is Debian-based.

The following configuration confirms:

    server {
        server_name _;
        listen 443 ssl;
        http2 on;
        ssl_certificate /etc/nginx/cert.pem;
        ssl_certificate_key /etc/nginx/key.pem;
        ssl_ciphers 'DEFAULT@SECLEVEL=0';
        location / { return 200 'OK - $ssl_protocol - $ssl_cipher\n'; }
    }

And testing with curl from inside the image:

# curl --ciphers 'DEFAULT@SECLEVEL=0' --tls-max 1.0 https://127.0.0.1:443/ -k
OK - TLSv1 - ECDHE-RSA-AES256-SHA

[thresheek]

Hi @Chokoabigail !

Have you been able to figure out the issue with your TLS setup?

[buchdag]

Hi @thresheek I'm facing the same issue with nginx 1.27, trying to re-enable TLSv1 and TLSv1.1 in nginx-proxy

The nginx configuration:

# mozilla-old.nginx-proxy.tld/
upstream mozilla-old.nginx-proxy.tld {
    # Container: nginx-proxy-old-1
    #     networks:
    #         nginx-proxy_default (reachable)
    #     IP address: 172.22.0.4
    #     exposed ports (first ten): 80/tcp
    #     default port: 80
    #     using port: 80
    server 172.22.0.4:80;
}
server {
    server_name mozilla-old.nginx-proxy.tld;
    access_log /var/log/nginx/access.log vhost;
    http2 on;
    listen 443 ssl ;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3;
    ssl_ciphers 'DEFAULT@SECLEVEL=0';
    ssl_prefer_server_ciphers on;
    ssl_session_timeout 5m;
    ssl_session_cache shared:SSL:50m;
    ssl_session_tickets off;
    ssl_certificate /etc/nginx/certs/nginx-proxy.tld.crt;
    ssl_certificate_key /etc/nginx/certs/nginx-proxy.tld.key;
    set $sts_header "";
    if ($https) {
        set $sts_header "max-age=31536000";
    }
    add_header Strict-Transport-Security $sts_header always;
    location / {
        proxy_pass http://mozilla-old.nginx-proxy.tld;
        set $upstream_keepalive false;
    }
}

Then from inside the container:

202fd55cb312:/app# curl --ciphers 'DEFAULT@SECLEVEL=0' --resolve mozilla-old.nginx-proxy.tld:443:127.0.0.1 --tls-max 1.0 https://mozilla-old.nginx-proxy.tld -k
curl: (35) OpenSSL/3.3.2: error:0A00042E:SSL routines::tlsv1 alert protocol version
202fd55cb312:/app# curl --ciphers 'DEFAULT@SECLEVEL=0' --resolve mozilla-old.nginx-proxy.tld:443:127.0.0.1 --tls-max 1.1 https://mozilla-old.nginx-proxy.tld -k
curl: (35) OpenSSL/3.3.2: error:0A00042E:SSL routines::tlsv1 alert protocol version
202fd55cb312:/app# curl --ciphers 'DEFAULT@SECLEVEL=0' --resolve mozilla-old.nginx-proxy.tld:443:127.0.0.1 --tls-max 1.2 https://mozilla-old.nginx-proxy.tld -k
<!DOCTYPE html>
[...] rest of the page

Same result from the outside using either nmap --script ssl-enum-ciphers, openssl s_client or curl.

[buchdag]

I think I found the issue, we have default values for ssl_protocols and ssl_ciphers that are defined outside of a server block and set to the Mozilla Intermediate TLS and ciphers configuration.

This seemingly prevent TLSv1 and TLSv1.1 from working even if ssl_protocols and ssl_ciphers are redefined in a subsequent server block.

@thresheek does that seem correct to you ?