Tux


Ubuntu Distribution Upgrade: Not enough free disk space

Recently, we tried to upgrade an Ubuntu 20.04 desktop to a 22.04. At some point in the update, we got the following error:

The upgrade has aborted. The upgrade needs a total of 10,6 G free space on disk '/'. Please free at least an additional 8201 M of disk space on '/'. Empty your trash and remove temporary packages of former installations using 'sudo apt-get clean'. The upgrade has aborted. The upgrade needs a total of 430 M free space on disk '/boot'. Please free at least an additional 38,4 M of disk space on '/boot'. You can remove old kernels using 'sudo apt autoremove' and you could also set COMPRESS=xz in /etc/initramfs-tools/initramfs.conf to reduce the size of your initramfs.

First of all, we tried to use the command apt autoremove to clear up some space, which unfortunately was not enough.

sudo apt autoremove;

Then to clear up some space, we needed to find remnant memories of older versions of the Kernel. To do so, we used the following command. The following command finds the current version of the kernel and shows the user the remaining packages that do not reflect the active kernel.

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d;/^linux-\(headers\|image\)/!d';

Then we removed all the headers and the images that we did not need using the command apt-get purge.

$ dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d;/^linux-\(headers\|image\)/!d'
linux-headers-5.13.0-52-generic
linux-headers-5.15.0-46-generic
linux-headers-generic-hwe-20.04
linux-image-5.15.0-46-generic
linux-image-generic-hwe-20.04

$ sudo apt-get -y purge linux-headers-5.13.0-52-generic linux-headers-5.15.0-46-generic linux-image-5.15.0-46-generic;

Doing so was enough to clear up the space that was needed for the upgrade to continue.


19th place for Cypriot Hackers in the European Cyber Security Competition. Cyprus won 19th place in the Pan-European Cyber Security Competition

The Cypriot Cybersecurity Team took 19th place in the Pan-European Cybersecurity Competition held in Vienna from September 12th to September 16th.

The competition was attended by 28 countries from Europe and Canada, the United States of America, the United Arab Emirates, Israel, and Serbia, with people aged 14-25 students, students, professionals, hackers, security researchers, and self-taught enthusiasts in the field of cyber security.

The Cypriot team was represented by Vassilis Charalambos (Team Leader), Andreas Tsouloupas, Odysseas Stavrou, Eleni Ioakeim, Christodoulos Sotiriou, Panagiotis Gabriel, Christos Falas, Joseph Modestou, Marios Kailis, and Evangelos Liudakis. The team was accompanied and trained by the coaches: Marios Nicolaidis, Christos Makridis, and Nikolas Markitanis. Simon Loizidis and George Michael represented Cyprus on behalf of the European Coordinating Committee.

The first three places were occupied by Denmark, Germany, and France.

The ECSC competition is an initiative of the European Network and Information Security Agency (ENISA) and aims to identify new talent in the field of cybersecurity, as well as encourage young people to pursue careers in the field.

The organization and the whole effort are supported by the Cyprus Computer Society, the Cypriot Cybersecurity Community CYberMouflons, and the organization is under the auspices of the Ministry of Defence, the Ministry of Education, Culture, Sports and Youth, the Cyprus Police, and the Digital Security Authority through the Office of the Communications Commissioner.

The participation of our National team would not be possible without the support of the sponsors: Adacom Cyber Security, Defense.com, Deloitte, European University Cyprus, Exness, Frederick University, Grant Thornton, KPMG, Odyssey Cybersecurity, Oracle Academy, Try Hack Me, University of Central Lancashire (UCLan) Cyprus and XM as well as supporters HostingB2B, MVPS.net, ICSI, Offensive Security, RedPoint, Robo Cy and SCP Academy, Silensec and Cyber Ranges.

More information on the websites, https://ecsc.eu/, https://www.ccsc.org.cy, and social networks.


Microsoft invented a new way to force users into using their online accounts

It became apparent that new Microsoft installations are getting increasingly aggressive, forcing users to create an online Microsoft account on their machines.

Please note that we created a new online Microsoft account in the end… We do not have a working solution to this issue.

Backstory: we purchased a new laptop that had Microsoft Windows 10 pre-installed. The first time we booted it, we did not want to sign in using a Microsoft online account, so we did not give internet to the laptop. Doing so allowed us to create a local account on the computer without associating it with an online account.

After several updates, we tried to install Firefox, and besides the usual annoying Microsoft advertisements about Bing, we got the following messages for Microsoft Windows S Mode.

For security and performance, this mode of Windows only runs Microsoft-verified apps
Initial notification of Microsoft S Mode – For security and performance, Windows 10 in S mode runs Microsoft-verified apps

After clicking on the “Learn More” button, we got the following:

Microsoft S Mode – Switch out prompt

Clicking on the “Get” button got us to the Microsoft Online Account login form…

Microsoft sign-in form appears when you try to switch out of S mode.

We then closed all windows, disabled internet access, and tried installing Firefox again. This time, we got the following message:

After disabling the internet connection, we tried to bypass the SmartScreen and the S mode settings

After clicking on the “Run” button, we got stopped again by the Microsoft Windows S Mode settings.

As this post mentioned, we eventually created a new online Microsoft account and used it to log in and disable Microsoft S Mode.


Participation of Cyprus in the European Cyber ​​Security Challenge ECSC 2022

Next Monday, September 12, 2022, the National Cyber ​​Security Team travels to Vienna to participate in the European Cyber ​​Security Competition 2022.

33 countries participate in the ECSC competition with people aged 14-25 pupils, students, professionals, hackers, security researchers, as well as self-taught in the field of cyber security.

The Cypriot delegation consists of Simon Loizidis (Team Leader), Vasilis Charalambous, Andreas Tsouloupas, Odysseas Stavrou, Eleni Ioakeim, Christodoulos Sotiriou, Panagioti Gavriil, Christos Falas, Joseph Modestou, Marios Kailis, and Evangelos Liudakis. The team will be accompanied by the mentors: Marios Nicolaides, Christos Makrides, and Nicolas Markitanis, and on behalf of the European Coordinating Committee, George Michael.

The corresponding CCSC Pancyprian competition is organized annually by the Cyprus Computer Society (CCS) and the CyberMouflons Hacking Community. CCSC 2022 is sponsored by the Ministry of Defence, the Ministry of Education, Culture, Sports and Youth, the Cyprus Police, and the Digital Security Authority through the Office of the Communications Commissioner.

CCSC 22 Sponsors: Adacom Cyber ​​Security, Defense.com, Deloitte, European University Cyprus, Exness, Frederick University, Grant Thornton, KPMG, Odyssey Cybersecurity, Oracle Academy, Try Hack Me, University of Central Lancashire (UCLan) Cyprus, and XM as well as supporters HostingB2B, MVPS.net, ICSI, Offensive Security, RedPoint, Robo Cy and SCP Academy, Silensec, Cyber ​​Ranges.

Good luck to the participants!

You can see the team’s official video clip here:

Information on the website https://www.ccsc.org.cy and social networks on Facebook (@CCSC.Cyprus) and Twitter (@CCSC_Cyprus).