Found the error Not allowed to load local resource: file:///etc/passwd while looking at infosec.pub’s communities page. There’s a community called “ignore me” that adds a few image tags trying to steal your passwd file.

You have to be extremely poorly configured for this to work, but the red flags you see should keep you on your toes for the red flags you don’t.

    • Greg Clarke@lemmy.ca
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      1 year ago

      Are you sure? What do you get when you run $ cat /etc/passwd in terminal? Just paste the results here 😇

      Edit: to anyone reading this on the future, don’t actually do this, it was a joke

      • fox@vlemmy.net
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        1 year ago

        yup pretty sure

        $ cat /etc/passwd
        fox:hunter2:1000:1000::/home/fox:/usr/bin/zsh
        

        😉

      • delial@lemmy.sdf.org
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        1 year ago

        Since you told me not to. There isn’t a risk on most linux systems; passwords were moved to /etc/shadow a long time ago. It only leaks the names of your users and largely useless info for most attackers:

        root:x:0:0:root:/root:/bin/bash
        daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
        bin:x:2:2:bin:/bin:/usr/sbin/nologin
        sys:x:3:3:sys:/dev:/usr/sbin/nologin
        sync:x:4:65534:sync:/bin:/bin/sync
        games:x:5:60:games:/usr/games:/usr/sbin/nologin
        man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
        lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
        mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
        news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
        uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
        proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
        www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
        backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
        list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
        irc:x:39:39:ircd:/run/ircd:/usr/sbin/nologin
        gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin
        nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
        _apt:x:100:65534::/nonexistent:/usr/sbin/nologin
        systemd-network:x:101:102:systemd Network Management,,,:/run/systemd:/usr/sbin/nologin
        systemd-resolve:x:102:103:systemd Resolver,,,:/run/systemd:/usr/sbin/nologin
        messagebus:x:999:999:System Message Bus:/:/usr/sbin/nologin
        systemd-timesync:x:998:998:systemd Time Synchronization:/:/usr/sbin/nologin
        systemd-coredump:x:997:997:systemd Core Dumper:/:/usr/sbin/nologin
        delial:x:1000:1000:,,,:/home/delial:/bin/bash
        sshd:x:103:65534::/run/sshd:/usr/sbin/nologin
        xrdp:x:104:110::/run/xrdp:/usr/sbin/nologin
        dictd:x:105:111:Dictd Server,,,:/var/lib/dictd:/usr/sbin/nologin
        nm-openvpn:x:106:112:NetworkManager OpenVPN,,,:/var/lib/openvpn/chroot:/usr/sbin/nologin
        sssd:x:107:113:SSSD system user,,,:/var/lib/sss:/usr/sbin/nologin
        
        • marvin@lemmy.sdf.org
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          1 year ago

          Well it’s not completely useless. It offers some insights into the system. Which service accounts exists, what usernames are used.

          If an attacker finds a valid username they can then start bruteforcing the password.

          From your account list we can see you have sshd and xrdp. Do they both provide the same kind of bruteforce protection? Are there any recent exploits for either?

          • delial@lemmy.sdf.org
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            1 year ago

            That’s why I said largely useless. An attacker can narrow down the attack surface by ignoring anything that can’t login, but that just leaves them with root and delial, and they already knew or could’ve guessed both of those pieces of information (in this context anyway).

            And as you noted when looking at the service accounts, they might be able to login or crack their way in via xrdp or sshd. So, unless you’re port-forwarding those protocols from the internet, how useful is that really? I would say largely useless. Assuming they port-scanned your public IP, they still need either an insecure config or an unpatched, remotely exploitable bug.

            That being said, you’re totally right. The average Linux user isn’t “administering” their system, so they probably aren’t following their distribution’s security mailing list, installing security patches as they’re released, and actually RTFM. It’s best for the average user to play it unbelievably safe.

            In this case, the machine isn’t actually running xrdp, and sshd doesn’t accept passwords or root logins. (Although, I need to setup knockd to protect that non-standard sshd port a bit more.) All passwords used on the system are random and longer than 32 characters. My router doesn’t port-forward to this machine, either.

            This has been an exercise of Cunningham’s Law for the benefit of those reading.