ncrack segmentation fault error specific to SSH service brute force

[triznut]

I receive the following error message when trying to brute force SSH services:

ncrack -v --user root -P /usr/share/wordlists/rockyou-custom.txt 10.xx.xx.xx:22

Starting Ncrack 0.6 ( http://ncrack.org ) at 2018-03-27 10:40 MDT

Segmentation fault

Dmesg Log:

[ 300.771692] ncrack[2222]: segfault at 8 ip 00007f8ac720b849 sp 00007ffd7b8e7140 error 4 in libcrypto.so.1.1[7f8ac714a000+262000]

[ithilgore]

Can you retry with the latest version of Ncrack (0.7 on github) compiled against OpenSSL 1.1?

[denevin]

@ithilgore Problem still exists in Ncrack 0.7 compiled against OpenSSL 1.1

[ghost]

I found a solution, try to save your file without .txt extension that's work for me, have a good day 👍

[doomguy]

Had the same issue today wit ncrack 0.5. (This is the version found in the fedora repos.)

I found that the wordlist needs to have a blank line at the end in order not to segfault.

[doomguy]

Just compiled ncrack 0.7 with openssl 1.1.0i-fips. Now I can't brute any ssh service anymore.

I tried 4 test cases in total:

• wordlist without extension and without trailing blank line
• wordlist without extension and with trailing blank line
• wordlist with extension and without trailing blank line
• wordlist with extension and with trailing blank line

I attached the dmesg log to this message. ncrack_segfault.txt

[same7ammar]

I found a solution, try to save your file without .txt extension that's work for me, have a good day 👍

i tired to rename file and extension but still facing same issue .

root@pen:~# ncrack -v -T 5 --user admin -P wordlist.txt 192.168.8.110:22

Starting Ncrack 0.6 ( http://ncrack.org ) at 2018-11-25 04:29 EST

Segmentation fault

[Velby]

ping, same issue here

[TheConen]

Is there anything new on this? I'm having the same issue.

[chanuniva]

just updating ncrack will resolve the issue(apt-get -y install ncrack). ncrack version 0.6 seems all affected.

[cldrn]

Hey @ithilgore ,

This bug still persists on ncrack 0.8. As mentioned on this thread, it does not segfault when the password list has an empty line.

[yoke88]

still segfault:

1. using password file without extension
2. using password with a empty line
3. patch with the pull request #108

seems defferent passwords cause segfault too ncrack version 0.8