[BUG / possible BUG] Stuck at Opossum test

[segrab]

I am running version testssl version 3.3dev from https://testssl.sh/dev/

Couldn't find anything related

Command line / docker command to reproduce

testssl -U FQDN

Expected behavior

Should check for possible vulnerabilities

Your system (please complete the following information):

• OS: Ubuntu 22.04.5 LTS
• Platform: Linux 6.8.0-1029-azure x86_64
• OpenSSL + bash: OpenSSL 1.0.2-bad (Mar 28 2025) [~179 ciphers], Using bash 5.1.16

Additional context

When testing for vulnerabilities on some sites it stucks at Opossum test and wont go further.

Can not provided tested sites because they are sensitive but seems to be related to citrix netscaler.
Tested against some netscaler gateways and always stuck at Opossum test.

Regards

[segrab]

Short Update.

If i let it long enough, the error "cat: -: Connection timed out" appears.

[drwetter]

Kind of was suspecting that it hangs. However looking shortly at the code... maybe you can help me?

I suspect it hangs around L1973 . Could you put "set -x" some where around that and check where the culprit is?

[segrab]

Sure, i hope this will help

[drwetter]

Okay, thanks!

In principle that can be fixed if the cat command is being put in the background and immediately after there'll be a wait_kill $! $((HEADER_MAXSLEEP * 10)) .

However, being stuck there means the host doesn't respond to the HTTP head command. Thus I´d rather like to understand why this is the case.

• Does curl -i -H "Upgrade: TLS/1.0" -I http://yourFQDN show the same behavior?
• Is there any specific HTTP header , HTML title of web page, cookie , etc. you can give me so that I can search for such a node out there in the net?

[drwetter]

see #2951 . Thanks for filing the bug!