NGINX Ingress controller security encryption overview and configuration - Container Service for Kubernetes

For workloads with strict in-transit security requirements, configure and verify TLS protocol versions and cipher suites for Nginx Ingress Controller.

Prerequisites

Ensure the following:

Nginx Ingress Controller is installed and running in your cluster. See Manage Nginx Ingress Controller components.
kubectl is configured to connect to the cluster. See Connect to an ACK cluster using kubectl.

TLS encryption settings

Configure TLS protocol versions and cipher suites with the ssl-protocols and ssl-ciphers fields in the nginx-configuration ConfigMap under the kube-system namespace.

Field	Description	Default value
`ssl-protocols`	The TLS protocol versions accepted by the ingress. TLS 1.2 and TLS 1.3 by default. See ssl-protocols.	`TLSv1.2 TLSv1.3`
`ssl-ciphers`	The cipher suites accepted by the ingress, in OpenSSL format. The default cipher suites support multiple TLS clients. To use more restrictive suites, set ssl-ciphers in the ConfigMap to override the default. Order determines algorithm priority — defaults prioritize PFS-capable suites. See ssl-ciphers.	`ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384`

Cipher suite order determines algorithm priority. The defaults prioritize PFS-capable suites — keep them unless you have specific security requirements.

After applying the configuration, verify it with testssl.sh or SSL Labs.

Update the ConfigMap

Console

Log on to the Container Service Management Console. In the left navigation pane, click Clusters.
On the Clusters page, click the name of your cluster. In the left navigation pane, choose Configurations > ConfigMaps.
On the ConfigMap page, select kube-system from the Namespace drop-down. Search for nginx-configuration in the Name search box. Find nginx-configuration and click Edit in the Actions column.
On the Edit page, click +Add. Enter the Name and Value, then click OK.

kubectl

Open the ConfigMap in your editor:

kubectl edit cm -n kube-system nginx-configuration

Add or update the ssl-protocols and ssl-ciphers fields:

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-configuration
  namespace: kube-system
data:
  ssl-protocols: "TLSv1.2 TLSv1.3"  # Only TLS 1.2 and TLS 1.3 are allowed.
  ssl-ciphers: "ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384"  # Default cipher suite list.

Verify TLS versions and cipher suites

Confirm the TLS configuration with either method.

Method 1: Download testssl.sh and run:

./testssl.sh <site-domain-name>

Weak cipher suites or deprecated TLS versions are highlighted in red. Expected output for a correctly configured ingress:

 Testing protocols via sockets except NPN+ALPN
 SSLv2      not offered (OK)
 SSLv3      not offered (OK)
 TLS 1      not offered
 TLS 1.1    not offered
 TLS 1.2    offered (OK)
 TLS 1.3    offered (OK): final
 NPN/SPDY   not offered
 ALPN/HTTP2 h2, http/1.1 (offered)
 Testing cipher categories
 NULL ciphers (no encryption)                  not offered (OK)
 Anonymous NULL Ciphers (no authentication)    not offered (OK)
 Export ciphers (w/o ADH+NULL)                 not offered (OK)
 LOW: 64 Bit + DES, RC[2,4] (w/o export)       not offered (OK)
 Triple DES Ciphers / IDEA                     not offered
 Obsolete CBC ciphers (AES, ARIA etc.)         not offered
 Strong encryption (AEAD ciphers)              offered (OK)
 Testing robust (perfect) forward secrecy, (P)FS -- omitting Null Authentication/Encryption, 3DES, RC4
 PFS is offered (OK)          TLS_AES_256_GCM_SHA384 TLS_CHACHA20_POLY1305_SHA256 ECDHE-RSA-AES256-GCM-SHA384 ECDHE-RSA-CHACHA20-POLY1305
                              TLS_AES_128_GCM_SHA256 ECDHE-RSA-AES128-GCM-SHA256
 Elliptic curves offered:     prime256v1 secp384r1 secp521r1 X25519 X448
 Finite field group:          ffdhe2048 ffdhe3072 ffdhe4096 ffdhe6144 ffdhe8192
 Testing server preferences
 Has server cipher order?     yes (OK) -- TLS 1.3 and below
 Negotiated protocol          TLSv1.3
 Negotiated cipher            TLS_AES_256_GCM_SHA384, 253 bit ECDH (X25519)
 Cipher order
    TLSv1.2:   ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES256-GCM-SHA384 ECDHE-RSA-CHACHA20-POLY1305
    TLSv1.3:   TLS_AES_256_GCM_SHA384 TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256
...

Method 2: Enter your domain in the SSL Labs SSL Server Test.

View configured cipher suites

View the active cipher suites in the Nginx configuration:

kubectl -n kube-system exec deploy/nginx-ingress-controller -- nginx -T | grep ssl_ciphers

Expected output:

Defaulted container "nginx-ingress-controller" out of: nginx-ingress-controller, init-sysctl (init)
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
        ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384';
nginx: configuration file /etc/nginx/nginx.conf test is successful

FAQ

Does Nginx Ingress Controller support Chinese cryptographic algorithms?

No. ACK Nginx Ingress Controller is based on the Kubernetes community ingress-nginx project and does not currently support Chinese cryptographic algorithms.

What cipher suites does Nginx Ingress support?

Nginx uses OpenSSL for encryption. To list available cipher suites, exec into the controller pod:

kubectl exec -it -n kube-system <nginx-ingress-pod-name> bash

Inside the container, run nginx -V to check the Nginx and OpenSSL versions:

nginx-ingress-controller-5c455d7d9f-nr7dd:/etc/nginx$ nginx -V

Expected output:

nginx version: nginx/1.21.6
built by gcc 12.2.1 20220924 (Alpine 12.2.1_git20220924-r10)
built with OpenSSL 3.1.3 19 Sep 2023 (running with OpenSSL 3.1.5 30 Jan 2024)
TLS SNI support enabled
configure arguments: --prefix=/usr/local/nginx --conf-path=/etc/nginx/nginx.conf --modules-path=/etc/nginx/modules --http-log-path=/var/log/nginx/access.log --error-log-path=/var/log/nginx/error.log --lock-path=/var/lock/nginx.lock --pid-path=/run/nginx.pid --http-client-body-temp-path=/var/lib/nginx/body --http-fastcgi-temp-path=/var/lib/nginx/fastcgi --http-proxy-temp-path=/var/lib/nginx/proxy --http-scgi-temp-path=/var/lib/nginx/scgi --http-uwsgi-temp-path=/var/lib/nginx/uwsgi --with-debug --with-compat --with-pcre-jit --with-http_ssl_module --with-http_stub_status_module --with-http_realip_module --with-http_auth_request_module --with-http_addition_module --with-http_geoip_module --with-http_gzip_static_module --with-http_sub_module --with-http_v2_module --with-stream --with-stream_ssl_module --with-stream_realip_module --with-stream_ssl_preread_module --with-threads --with-http_secure_link_module --with-http_gunzip_module --with-file-aio --without-mail_pop3_module --without-mail_smtp_module --without-mail_imap_module --without-http_uwsgi_module --without-http_scgi_module --with-cc-opt='-g -O3 -flto -fPIE -fstack-protector-strong -Wformat -Werror=format-security -Wno-deprecated-declarations -fno-strict-aliasing -D_FORTIFY_SOURCE=2 --param=ssp-buffer-size=4 -DTCP_FASTOPEN=23 -fPIC -I/root/.hunter/_Base/d45d77d/aab92d8/3b7ee27/Install/include -Wno-cast-function-type -m64 -mtune=generic' --with-ld-opt='-flto -fPIE -fPIC -pie -Wl,-z,relro -Wl,-z,now -L/root/.hunter/_Base/d45d77d/aab92d8/3b7ee27/Install/lib' --user=www-data --group=www-data --add-module=/tmp/build/ngx_devel_kit-0.3.2 --add-module=/tmp/build/set-misc-nginx-module-0.33 --add-module=/tmp/build/headers-more-nginx-module-0.34 --add-module=/tmp/build/ngx_http_substitutions_filter_module-b8a71eacc7f986ba091282ab8b1bbbc6ae1807e0 --add-module=/tmp/build/lua-nginx-module-0.10.25 --add-module=/tmp/build/stream-lua-nginx-module-0.0.13 --add-module=/tmp/build/lua-upstream-nginx-module-8aa93ead98ba2060d4efd594ae33a35d153589bf --add-dynamic-module=/tmp/build/nginx-http-auth-digest-1.0.0 --add-dynamic-module=/tmp/build/nginx-opentracing-0.19.0/opentracing --add-dynamic-module=/tmp/build/ModSecurity-nginx-1.0.3 --add-dynamic-module=/tmp/build/ngx_http_geoip2_module-a26c6beed77e81553686852dceb6c7fdacc5970d --add-dynamic-module=/tmp/build/ngx_brotli

Run openssl ciphers to list all supported cipher suites:

nginx-ingress-controller-5c455d7d9f-nr7dd:/etc/nginx$ openssl ciphers

Expected output:

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES256-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES128-SHA:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:AES256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:AES128-GCM-SHA256:PSK-AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:ECDHE-PSK-AES256-CBC-SHA384:ECDHE-PSK-AES256-CBC-SHA:SRP-RSA-AES-256-CBC-SHA:SRP-AES-256-CBC-SHA:RSA-PSK-AES256-CBC-SHA384:DHE-PSK-AES256-CBC-SHA384:RSA-PSK-AES256-CBC-SHA:DHE-PSK-AES256-CBC-SHA:AES256-SHA:PSK-AES256-CBC-SHA384:PSK-AES256-CBC-SHA:ECDHE-PSK-AES128-CBC-SHA256:ECDHE-PSK-AES128-CBC-SHA:SRP-RSA-AES-128-CBC-SHA:SRP-AES-128-CBC-SHA:RSA-PSK-AES128-CBC-SHA256:DHE-PSK-AES128-CBC-SHA256:RSA-PSK-AES128-CBC-SHA:DHE-PSK-AES128-CBC-SHA:AES128-SHA:PSK-AES128-CBC-SHA256:PSK-AES128-CBC-SHA

Run openssl ciphers -tls1_2 -v to list TLS 1.2 cipher suites:

nginx-ingress-controller-5c455d7d9f-nr7dd:/etc/nginx$ openssl ciphers -tls1_2 -v

Expected output:

TLS_AES_256_GCM_SHA384         TLSv1.3 Kx=any      Au=any   Enc=AESGCM(256)            Mac=AEAD
TLS_CHACHA20_POLY1305_SHA256   TLSv1.3 Kx=any      Au=any   Enc=CHACHA20/POLY1305(256) Mac=AEAD
TLS_AES_128_GCM_SHA256         TLSv1.3 Kx=any      Au=any   Enc=AESGCM(128)            Mac=AEAD
ECDHE-ECDSA-AES256-GCM-SHA384  TLSv1.2 Kx=ECDH     Au=ECDSA Enc=AESGCM(256)            Mac=AEAD
ECDHE-RSA-AES256-GCM-SHA384    TLSv1.2 Kx=ECDH     Au=RSA   Enc=AESGCM(256)            Mac=AEAD
DHE-RSA-AES256-GCM-SHA384      TLSv1.2 Kx=DH       Au=RSA   Enc=AESGCM(256)            Mac=AEAD
ECDHE-ECDSA-CHACHA20-POLY1305  TLSv1.2 Kx=ECDH     Au=ECDSA Enc=CHACHA20/POLY1305(256) Mac=AEAD
ECDHE-RSA-CHACHA20-POLY1305    TLSv1.2 Kx=ECDH     Au=RSA   Enc=CHACHA20/POLY1305(256) Mac=AEAD
...

How do I get the OpenSSL name for an IANA/RFC cipher suite name?

Cipher suites have two naming conventions: OpenSSL (e.g., AES128-SHA) and IANA/RFC (e.g., TLS_RSA_WITH_AES_128_CBC_SHA).

To convert an IANA name to its OpenSSL equivalent, use either method:

Look up the mapping in the OpenSSL–IANA cipher name mapping table.

Run openssl ciphers -convert <IANA-cipher-suite-name> inside the controller container. For example:

nginx-ingress-controller-5c455d7d9f-nr7dd:/etc/nginx$ openssl ciphers -convert TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
OpenSSL cipher name: ECDHE-RSA-AES128-GCM-SHA256