Today I elected to run a vulnerability scan against our new instance of the docker-traefik2-acme-host configuration that’s running on The command I used, and the results, are posted below.

╭─islandora@dgdockerx ~
╰─$ /home/islandora/

###########################################################       3.0rc4 from

      This program is free software. Distribution and
             modification under GPLv2 permitted.

       Please file bugs @


 Using "OpenSSL 1.0.2-chacha (1.0.2k-dev)" [~183 ciphers]
 on dgdockerx:/home/islandora/
 (built: "Jan 18 17:12:17 2019", platform: "linux-x86_64")

 Start 2020-06-11 17:33:25        -->> ( <<--

 rDNS (
 Service detected:       HTTP

 Testing protocols via sockets except NPN+ALPN

 SSLv2      not offered (OK)
 SSLv3      not offered (OK)
 TLS 1      offered
 TLS 1.1    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                     offered (NOT ok)
 Average: SEED + 128+256 Bit CBC ciphers       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-AES256-SHA
                              ECDHE-RSA-CHACHA20-POLY1305 TLS_AES_128_GCM_SHA256 ECDHE-RSA-AES128-GCM-SHA256 ECDHE-RSA-AES128-SHA
 Elliptic curves offered:     prime256v1 secp384r1 secp521r1 X25519

 Testing server preferences

 Has server cipher order?     yes (OK) -- only for < TLS 1.3
 Negotiated protocol          TLSv1.3
 Negotiated cipher            TLS_AES_256_GCM_SHA384, 253 bit ECDH (X25519)
 Cipher order
    TLSv1.3:   TLS_AES_256_GCM_SHA384 TLS_CHACHA20_POLY1305_SHA256 TLS_AES_128_GCM_SHA256

 Testing server defaults (Server Hello)

 TLS extensions (standard)    "session ticket/#35" "renegotiation info/#65281" "EC point formats/#11" "supported versions/#43"
                              "key share/#51" "application layer protocol negotiation/#16"
 Session Ticket RFC 5077 hint no -- no lifetime advertised
 SSL Session ID support       yes
 Session Resumption           Tickets no, ID: no
 TLS clock skew               Random values, no fingerprinting possible
 Signature Algorithm          SHA256 with RSA
 Server key size              RSA 2048 bits
 Server key usage             Digital Signature, Key Encipherment
 Server extended key usage    TLS Web Server Authentication, TLS Web Client Authentication
 Serial / Fingerprints        035B28222F66FCE82AB86834D316C249EDB3 / SHA1 385FFF215983EFA46B2CAFCA6768356348475307
                              SHA256 F2A91B6B1BE83479550EE679AEA78B9551CA00D1D5BC0DA4B80D1FA1B4E3ED25
 Common Name (CN)    (CN in response to request w/o SNI: TRAEFIK DEFAULT CERT)
 subjectAltName (SAN)
 Issuer                       Let's Encrypt Authority X3 (Let's Encrypt from US)
 Trust (hostname)             Ok via SAN and CN (SNI mandatory)
 Chain of trust               NOT ok (chain incomplete)
 EV cert (experimental)       no
 "eTLS" (visibility info)     not present
 Certificate Validity (UTC)   88 >= 30 days (2020-06-10 11:51 --> 2020-09-08 11:51)
 # of certificates provided   1
 Certificate Revocation List  --
 OCSP URI           
 OCSP stapling                not offered
 OCSP must staple extension   --
 DNS CAA RR (experimental)    not offered
 Certificate Transparency     yes (certificate extension)

 Testing HTTP header response @ "/"

 HTTP Status Code             200 OK
 HTTP clock skew              0 sec from localtime
 Strict Transport Security    not offered
 Public Key Pinning           --
 Server banner                nginx/1.17.10
 Application banner           --
 Cookie(s)                    (none issued at "/")
 Security headers             --
 Reverse Proxy banner         --

 Testing vulnerabilities

 Heartbleed (CVE-2014-0160)                not vulnerable (OK), no heartbeat extension
 CCS (CVE-2014-0224)                       not vulnerable (OK)
 Ticketbleed (CVE-2016-9244), experiment.  not vulnerable (OK), reply empty
 ROBOT                                     not vulnerable (OK)
 Secure Renegotiation (CVE-2009-3555)      not vulnerable (OK)
 Secure Client-Initiated Renegotiation     not vulnerable (OK)
 CRIME, TLS (CVE-2012-4929)                not vulnerable (OK)
 BREACH (CVE-2013-3587)                    no HTTP compression (OK)  - only supplied "/" tested
 POODLE, SSL (CVE-2014-3566)               not vulnerable (OK)
 TLS_FALLBACK_SCSV (RFC 7507)              Downgrade attack prevention supported (OK)
 SWEET32 (CVE-2016-2183, CVE-2016-6329)    VULNERABLE, uses 64 bit block ciphers
 FREAK (CVE-2015-0204)                     not vulnerable (OK)
 DROWN (CVE-2016-0800, CVE-2016-0703)      not vulnerable on this host and port (OK)
                                           make sure you don't use this certificate elsewhere with SSLv2 enabled services
                                  could help you to find out
 LOGJAM (CVE-2015-4000), experimental      not vulnerable (OK): no DH EXPORT ciphers, no DH key detected with <= TLS 1.2
                                           VULNERABLE -- but also supports higher protocols  TLSv1.1 TLSv1.2 (likely mitigated)
 LUCKY13 (CVE-2013-0169), experimental     potentially VULNERABLE, uses cipher block chaining (CBC) ciphers with TLS. Check patches
 RC4 (CVE-2013-2566, CVE-2015-2808)        no RC4 ciphers detected (OK)

 Testing 370 ciphers via OpenSSL plus sockets against the server, ordered by encryption strength

Hexcode  Cipher Suite Name (OpenSSL)       KeyExch.   Encryption  Bits     Cipher Suite Name (IANA/RFC)
 x1302   TLS_AES_256_GCM_SHA384            ECDH 253   AESGCM      256      TLS_AES_256_GCM_SHA384
 x1303   TLS_CHACHA20_POLY1305_SHA256      ECDH 253   ChaCha20    256      TLS_CHACHA20_POLY1305_SHA256
 xc030   ECDHE-RSA-AES256-GCM-SHA384       ECDH 521   AESGCM      256      TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
 xc014   ECDHE-RSA-AES256-SHA              ECDH 521   AES         256      TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
 xcca8   ECDHE-RSA-CHACHA20-POLY1305       ECDH 521   ChaCha20    256      TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
 x9d     AES256-GCM-SHA384                 RSA        AESGCM      256      TLS_RSA_WITH_AES_256_GCM_SHA384
 x35     AES256-SHA                        RSA        AES         256      TLS_RSA_WITH_AES_256_CBC_SHA
 x1301   TLS_AES_128_GCM_SHA256            ECDH 253   AESGCM      128      TLS_AES_128_GCM_SHA256
 xc02f   ECDHE-RSA-AES128-GCM-SHA256       ECDH 521   AESGCM      128      TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
 xc013   ECDHE-RSA-AES128-SHA              ECDH 521   AES         128      TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
 x9c     AES128-GCM-SHA256                 RSA        AESGCM      128      TLS_RSA_WITH_AES_128_GCM_SHA256
 x2f     AES128-SHA                        RSA        AES         128      TLS_RSA_WITH_AES_128_CBC_SHA
 xc012   ECDHE-RSA-DES-CBC3-SHA            ECDH 521   3DES        168      TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
 x0a     DES-CBC3-SHA                      RSA        3DES        168      TLS_RSA_WITH_3DES_EDE_CBC_SHA

 Running client simulations (HTTP) via sockets

 Android 4.2.2                TLSv1.0 ECDHE-RSA-AES256-SHA, 521 bit ECDH (P-521)
 Android 4.4.2                TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 521 bit ECDH (P-521)
 Android 5.0.0                TLSv1.2 ECDHE-RSA-AES256-SHA, 521 bit ECDH (P-521)
 Android 6.0                  TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 256 bit ECDH (P-256)
 Android 7.0                  TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305, 253 bit ECDH (X25519)
 Chrome 65 Win 7              TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 253 bit ECDH (X25519)
 Chrome 70 Win 10             TLSv1.3 TLS_AES_128_GCM_SHA256, 253 bit ECDH (X25519)
 Firefox 59 Win 7             TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 253 bit ECDH (X25519)
 Firefox 62 Win 7             TLSv1.2 ECDHE-RSA-AES128-GCM-SHA256, 253 bit ECDH (X25519)
 IE 6 XP                      No connection
 IE 7 Vista                   TLSv1.0 AES128-SHA, No FS
 IE 8 Win 7                   TLSv1.0 AES128-SHA, No FS
 IE 8 XP                      TLSv1.0 DES-CBC3-SHA, No FS
 IE 11 Win 7                  TLSv1.2 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
 IE 11 Win 8.1                TLSv1.2 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
 IE 11 Win Phone 8.1          TLSv1.2 AES128-SHA, No FS
 IE 11 Win 10                 TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Edge 13 Win 10               TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Edge 13 Win Phone 10         TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Edge 15 Win 10               TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 253 bit ECDH (X25519)
 Safari 9 iOS 9               TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Safari 9 OS X 10.11          TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Safari 10 OS X 10.12         TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Apple ATS 9 iOS 9            TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 Tor 17.0.9 Win 7             TLSv1.0 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
 Java 6u45                    No connection
 Java 7u25                    TLSv1.0 ECDHE-RSA-AES128-SHA, 256 bit ECDH (P-256)
 Java 8u161                   TLSv1.2 ECDHE-RSA-AES256-SHA, 256 bit ECDH (P-256)
 Java 9.0.4                   TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)
 OpenSSL 1.0.1l               TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 521 bit ECDH (P-521)
 OpenSSL 1.0.2e               TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 256 bit ECDH (P-256)

 Done 2020-06-11 17:34:48 [  85s] -->> ( <<--

Controling TLS Ciphers

In previous server configs that used Traefik v1.x I was able to eliminate some potential vulnerabilities by removing old, weak ciphers. In that old environment I used a few command: options in the docker-compose.yml file along with a declaration of stronger ciphers in a traefik.toml file. That config change is documented in Removing Traefik Weak Ciphers.

In our new configuration, which uses Traefik v2.x, TLS cipher control is quite different. I used this post as guidance and subsequently ended up with these modified files:


version: "3.3"

    image: traefik:2.2.1
    container_name: traefik
    hostname: traefik
    restart: unless-stopped
      - no-new-privileges:true
      - proxy
      traefik.enable: true
      # next 4 lines...universal http --> https redirect per
      traefik.http.routers.http-catchall.rule: hostregexp(`{host:[a-z-.]+}`)
      traefik.http.routers.http-catchall.entrypoints: web
      traefik.http.routers.http-catchall.middlewares: redirect-to-https
      traefik.http.middlewares.redirect-to-https.redirectscheme.scheme: websecure
      # now the Traefik-specific dashboard stuff
      traefik.http.middlewares.traefik-auth.basicauth.users: admin:$$2y$$05$$pJEzHJBzfoYYS7/hGAedcOP8XdsqNXE7j.LHFBVjueASOqOvvjGOy
      traefik.http.routers.traefik-secure.entrypoints: websecure
      traefik.http.routers.traefik-secure.rule: Host(`${HOST}`) && (PathPrefix(`/api`) || PathPrefix(`/dashboard`))
      traefik.http.routers.traefik-secure.middlewares: traefik-auth
      traefik.http.routers.traefik-secure.tls: true
      traefik.http.routers.traefik-secure.service: api@internal
      traefik.http.routers.traefik-secure.tls.options: default
      - 80:80
      - 443:443
      - 8080:8080
      - /etc/localtime:/etc/localtime:ro
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - ../certs:/certs

    external: true

Note that in the above file I also changed the labels: syntax and removed a number of cumbersome quotation marks while doing so.


    minVersion = "VersionTLS13"

    minVersion = "VersionTLS12"
    cipherSuites = [

No Effect

Unfortunately, as you can see in the output at the top of this post, two potential vulnerabilities remain. Still, this new syntax should enable me to take control of TLS configuration if it does become necessary.

And that’s a wrap. Until next time…