I’ve been trying to solve a homework question in a beginner infosec class, and I was stumped on an issue and I didn’t really know of the right place to ask. If it isn’t then please let me know.
Given the following ports,
if somebody was developing malware, which would be the most likely to be used by it to bypass the firewall?
I know that 53 and 443 are DNS and HTTPS respectively.
My way of thinking about the problem is that it’s likely a firewall would be set up to not drop incoming HTTPS traffic so that would be the best one to develop malware for, but I feel like there’s possibly a trick to the question I’m missing. Also it’s probably possible to eliminate UDP 8080 because it falls out of the commonly used UDP service range, meaning it’s likely to be blocked by default.
Any insight or explanation would be helpful. Thanks!
I’m at my wits end here. I’m running 19.04 in dualboot(same SSD) with win 10.
On win10 everything is peachy; HDMI and mini display both work perfectly.
Come to Ubuntu 19.04, everything fails. Neither port works(xrandr never pulls up hdmi port as below):
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192 eDP-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 344mm x 193mm 1920x1080 144.00*+ 60.01 60.00 59.97 59.96 59.93 1680x1050 84.94 74.89 69.88 59.95 59.88 1600x1024 60.17 1400x1050 85.00 74.76 70.00 59.98 1600x900 59.99 59.94 59.95 59.82 1280x1024 85.02 75.02 60.02 1440x900 59.89 1400x900 59.96 59.88 1280x960 85.00 60.00 1440x810 60.00 59.97 1368x768 59.88 59.85 1360x768 59.80 59.96 1280x800 59.99 59.97 59.81 59.91 1152x864 100.00 85.06 85.00 75.00 75.00 70.00 60.00 1280x720 60.00 59.99 59.86 59.74 1024x768 85.00 75.05 60.04 85.00 75.03 70.07 60.00 1024x768i 86.96 960x720 85.00 75.00 60.00 928x696 75.00 60.05 896x672 75.05 60.01 1024x576 59.95 59.96 59.90 59.82 960x600 59.93 60.00 832x624 74.55 960x540 59.96 59.99 59.63 59.82 800x600 85.00 75.00 70.00 65.00 60.00 85.14 72.19 75.00 60.32 56.25 840x525 85.02 74.96 69.88 60.01 59.88 864x486 59.92 59.57 800x512 60.17 700x525 85.08 74.76 70.06 59.98 800x450 59.95 59.82 640x512 85.02 75.02 60.02 720x450 59.89 700x450 59.96 59.88 640x480 85.09 60.00 85.01 72.81 75.00 59.94 720x405 59.51 58.99 720x400 85.04 684x384 59.88 59.85 680x384 59.80 59.96 640x400 59.88 59.98 85.08 576x432 100.11 85.15 85.09 75.00 75.00 70.00 60.06 640x360 59.86 59.83 59.84 59.32 640x350 85.08 512x384 85.00 75.03 70.07 60.00 512x384i 87.06 512x288 60.00 59.92 416x312 74.66 480x270 59.63 59.82 400x300 85.27 72.19 75.12 60.32 56.34 432x243 59.92 59.57 320x240 85.18 72.81 75.00 60.05 360x202 59.51 59.13 360x200 85.04 320x200 85.27 320x180 59.84 59.32 320x175 85.27
And I’ve tried everything Google has. All failed. I installed and switched to LightDM, no use. I reinstalled, have gdm3 only running, no use. Any ideas? This is getting super frustrating 🙁
Connecting the laptop to my dell monitor brings up the message from the monitor:
No hdmi signal from your device
ADD: I’ve switched back from proprietary nvidia-driver-418 to noveau drivers, with no luck either. I opened nvidia settings and am currently running on the iGPU selection.
how to know the version, configuration files,open ports and task purpose.
debian based os
I have an MSI gs63vr with 3 USB3 ports and 1 USB2 port. Two of the USB3 ports stopped working (the ones in the back) but the other 2 work just fine. I have tried editing /etc/default/grub many times, to no avail.
The ports themselves don’t seem to be the problem, I can charge devices with them just fine, they just aren’t detected by ubuntu (I checked lsusb to make sure).
Any suggestions would be greatly appreciated!
I had Virtualmin running perfectly on my Ubuntu 18.04 I set a new internal static IP (Before it was DHCP) with netplan as following:
network: version: 2 renderer: networkd ethernets: enp6s0: dhcp4: no addresses: [192.168.2.1/22] gateway4: 192.168.1.1 nameservers: addresses: [184.108.40.206,220.127.116.11]
After that I forwarded all the necessary ports in my router. The router had a submask 255.255.255.0 so I changed it to 255.255.254.0
Now: the ports
3306 are still reachable and the ports
20000 are closed now/ Err_Conn_Refused (Checked with https://www.yougetsignal.com/tools/open-ports/) Before the IP change, all these ports were open and running.
doesn’t work either from a local network computer
Firewall seems to be OK, I tried to reinstall Virtualmin in the hope that it would reconfigure it correctly, no luck. I also tried to restore it and use dhcp again, but it’s still the same error. I assigned 10 Gb ram to virtualmin, so it shouldn’t be this either. Virtualmin is up and running, as far as I can understand.
USB ports on the right-hand side of my laptop don’t work on my laptop when Ubuntu is being used. (The ones on the left work!!) USB ports on the left-hand side of my laptop don’t work on the same laptop when Windows is being used. (The ones on the right work!!)
Is this related?
Ubuntu is my primary OS and I want all the USB ports to work with it. Any suggestions?
All of my 3 ports on my dell xps-13-9380-laptop don’t work anymore. These are the specs of my laptop:
I tried to update my BIOS by following this instructions: https://www.dell.com/support/article/us/en/19/sln171755/updating-the-dell-bios-in-linux-and-ubuntu-environments?lang=en
I also read in this post that downloading the update to the firmware would fix it: https://www.dell.com/community/Linux-General/Dell-XPS-13-9380-Thunderbolt-3-USB-Type-C-stopped-working/m-p/7249401#M16608
However, it says I need to download the .exe file to a USB stick. Since all my ports don’t work, I can’t do that, obviously.
I ran this command in my terminal
and got this result:
No upgrades for XPS 13 9380 System Firmware, current is 0.1.6.0: 0.1.6.0=same, 0.1.5.0=older, 0.1.4.0=older, 0.1.3.2=older, 0.1.2.1=older
I assume my firmware is uptodate?
What else can I do other than sending it back to DELL or resetting to factory settings and installing everything again?
I was told by Amazon that my ports are open to public 0.0.0.0/0 . But still no idea on how to closed. Kindly help.
I had setup iptables and other rules, but this quite new for me.
The below is the text from Amazon—
We see that you’ve denied outbound connections to the IP of the destination domain , however in reviewing your Amazon EC2 instance(s), it appears you have left several ports open to the public (0.0.0.0/0). Leaving ports open like this can leave your instance vulnerable to compromise and unwanted network activity in general.
TCP 22 0.0.0.0/0
TCP 80 0.0.0.0/0
TCP 443 0.0.0.0/0
Purely for research purposes used nmap to check security of my application deployed to Firebase. However, there some questions which I can’t understand:
- Why Firebase has open so many ports? Something like few hundreds.
- Almost on every port I’m getting an error
auth-owners: ERROR: Script execution failed without any information about it. Why is that? The only one which gives some information are the following ports: 80, 443, 5269, and 65389.
- Is TCP Sequence Prediction difficulty=17 and Network Distance 2 hops a good or bad result?
- What means ssl-date: TLS randomness does not represent time?
- What means IP ID Sequence Generation: Incremental?
- What are Aggressive OS guesses?
- I could see the open few hundreds of ports only after first scan, later on couldn’t replicate this. Is it possible that Firebase/Google closed the ports or blocked me for some of them? In second scan and every other I could see only information about open ports 80, and 443 with a log “Not shown: 998 filtered ports”.
- I did test this on Kali Linux using VirtualBox. In the nmap output I can see Running: Oracle Virtualbox, OS CPE: cpe:/o:oracle:virtualbox, OS details: Oracle Virtualbox, is it about my system or the scanned website hsoted on Firebase?
Even answers for some of this questions would be already really appreciated!
I was recently given an old computer (HP Pavilon Dm1 – I think it’s about 6 years old). All 3 USB ports on the computer are broken. So I have to install Ubuntu through Internet network adapter boot, but I’m a little lost how to do that. I was planning to install Ubuntu 19.04 to this old computer on SSD drive.
How can I install Ubuntu on a device with broken USB ports?