Questions tagged [security]
Security covers a wide-ranging set of topics including Users, Permissions, Authentication, Authorisation, Upgrades, Firewalling, Hardening, etc.
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Upgrade OpenSSH from v8.9 to v9.3 on 22.04.2 LTS?
I'm working on shoring up some vulnerabilities in our environment, and one of them is that we're on OpenSSH 8.9. Our security team has advised us to upgrade to 9.3, but I'm not seeing anything ...
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Patch management and cautious upgrades
My company runs a handful of Ubuntu servers which are considered mission critical. We can only take them offline for maintenance on very rare occasions. We have had problems in the past with the ...
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11
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Problem when trying to use aireplay-ng and mdk3 with airgeddon
When i was trying out evil twin access point attack on my network using airgeddon everything went smoothly except when my fake ap is up airgeddon isn't able to do deauthentication attack so i tried ...
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Functiaonality Problems After Latest Security Update [closed]
After today's security update, (053123strong text) and restart we began experiencing functionality problems, (errors opening external hard drives,commands not recogonized, loss of searchable desktop ...
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can user under www-data (PHP) escalate privileges by only knowing root password
The scenario is Ubuntu system with web server:
SSH Disabled
User doesn't have any terminal access
UFW enabled only HTTP and HTTPS allowed
PHP and Apache ran under www-data
www-data not added to ...
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56
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Future Security Update to openssh-server on Ubuntu Server 20.04 LTS?
As per:
https://launchpad.net/ubuntu/focal/+source/openssh/+changelog
and
https://ubuntu.com/blog/what-is-an-ubuntu-lts-release
and
https://ubuntu.com/about/release-cycle
" For each Ubuntu LTS ...
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2
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133
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Give user permission to read all directories and files
I'm a newbie, trying to create an user in Ubuntu Server 22.04, with reading permissions to all existing directories and files, so it could backup everything copying them via SFTP to the backup server (...
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Can I use PHP 7.4.x with Ubuntu 20.04
This is a question to better understand security update policy of the Ubuntu LTS distributions.
I understand that a certain Ubuntu version (such as 20.04 LTS) will not upgrade from PHP 7.4 to PHP 8.x ...
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Ubuntu 16.04 ESM / 18.04 ESM / 20.04 ESM / 22.04 ESM / 22.10 : FFmpeg vulnerabilities (USN-5958-1) after running nessus scan [duplicate]
So I have run several nessus scans to check for vulnerabilities on my ubuntu 20.04 setup and I keep getting this vulnerability.
I have followed this: https://ubuntu.com/security/notices/USN-5958-1 and ...
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85
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Security problem with Apache on Ubuntu 22.04
We use the last version of apache available on Ubuntu 22.04 (apache 2.4.52-1ubuntu4.5)
Our Vulnerability Scanner says that we have some level 5 and 4 vulnerabilities and we should evolve to last ...
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Is it okay to use the same pw for root and secure boot?
If I install with secure boot enabled I’m asked to set a pw which I’m told I won’t need often. Is it safe to use the same pw as for root?
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75
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Linux IMA(Integrity Measurement Architecture) is not calculating hash of executables
I am trying to use IMA in Ubuntu Desktop 22.04; the kernel version is 5.19.0-41-generic. I have verified that the following flags are present in the config file:
CONFIG_IMA=y
...
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0
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53
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Ubuntu Pro Withholding Security Updates [duplicate]
This has been talked about many times over the past few months, but I wanted to mention some specific packages that are available only through Ubuntu Pro, despite being high/critical security ...
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Secure boot & 'Device Security'
about 3 days ago I bought a brand new system and did a clean install of 23.04.
I did not have secure boot enabled. I then spent the next 3 days installing software to get my system up to a fully ...
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1
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32
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Chages to sshd_config not disable password only login
I have Ubuntu 22.04.2 LTS installed as a virtual machine (Windows Hyper-V). I am making the following changes to /etc/ssh/sshd_config
PermitRootLogin prohibit-password
PubkeyAuthentication yes
...
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30
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How can i whitelist one specific device using udev rule and block everything else?
I want to whitelist a USB Touch screen and block everything else. I have written hundreds of UDEV rules but none of them seem to work. I can block every single connected USB device but can't find a ...
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2
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107
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Why are kernel updates no longer categorized as "security updates" in focal?
After upgrading to Focal, I noticed that kernel updates show up in the GUI under "other updates" instead of "security updates". This can lead to delayed notification of critical ...
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26
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Opening laptop shows regular screen for split second before log-in
Upon opening my laptop, the screen always flickers to the regular desktop with all the windows open and readable before going to the log-in screen.
I'm on a ThinkPad E470 currently running Ubuntu 22....
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1
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Connectivity Checking notation is concerning
Under Settings → Privacy → Connectivity, I found Ubuntu provides a short notation, the second half of which concerns me (highlighting my own):
Connectivity checking is used to detect connection ...
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1
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1
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50
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Password protect controls (not locking)
I search for a way to lock the controls (mouse and keyboard) while still showing the applications on the screen.
I think about something where I press an key combination to de/-activate the mode and ...
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4
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228
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Is Lubuntu as safe as Ubuntu?
I have to format some USB that could be infected. I know that all Linux systems are pretty safe so I shouldn't worry so much, but I would like to be as safe as possible (even if I know that is ...
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CVE Patching assistance [duplicate]
Version - 22.04.2 LTS
I am new to the Linux and was hoping to get some assistance regarding CVE patching.I can see plenty of CVE's which I need to address but I am not sure how to patch it.
I know the ...
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object 'libgtk3-nocsd.so.0' from LD_PRELOAD cannot be preloaded when running chromium
Problem description
When I run chromium in a bash shell, I get this message: ERROR: ld.so: object 'libgtk3-nocsd.so.0' from LD_PRELOAD cannot be preloaded (failed to map segment from shared object): ...
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1
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Install only Security packages in Ubuntu
I hope you're doing fine,
I'm looking for a way to install manually only security updates in an ubuntu machine
Anyone can help? thanks
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1
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Restricting folder interaction of a user with root privileges
Often times when creating an Ubuntu Linux image, rather than giving an administrator root access, a new user is created with root privileges. Let's call this new user "root_2".
# adduser ...
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66
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Apparmor full system implementation help
I am trying to implement Apparmor full system implementation on Ubuntu Bionic in AWS EC2 instances.
https://gitlab.com/apparmor/apparmor/-/wikis/FullSystemPolicy#distribution
My goal is employ a deny-...
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0
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42
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codeanywhere disallowed host issue
I am trying to use codeanywhere from ubuntu Mozilla
firebox browser. Facing following error while running Django web app from codeanywhere.
DisallowedHost at /
Invalid HTTP_HOST header: 'port-3000-...
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0
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18
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How to block more than 3 ping requests from a host through iptables?
i want to block more than 3 ping echo-requests for demonstration purpose of my college practical, and i am unable to do so using the following rules in my firewall.
iptables -A INPUT -p icmp --icmp-...
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1
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87
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USN-5931-1 Why is this security patch only for ESM/ Ubuntu Pro
18.04 LTS still has general support until April 2023, the patch for USN-5931-1 was released March 7th 2023. As march is before April, and this is a security patch, this should have been included in ...
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2
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215
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Unattended-upgrades working correctly?
First off - I'm new to both ubuntu and the forum so please go easy on me this time!
I know questions about unattended-upgrades are often asked, and this one here looks possibly identical to my ...
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0
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59
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Block ips from certain country and security
I have an Ubuntu Server 22.04 with Nginx installed along with a laravel application.
When I view the access logs I can see a lot of attempts from a certain country to exploit my server and application....
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Deactivation of the possibility to deactivate 2FA via rescue mode (linux) - 2FA PAM module it doesn't make sense
I got interested in 2FA to log in for linux os ( PAM google authentificator)
The problem is that from the rescue boot level it can be easily disabled which means that if someone has physical access to ...
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2
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Secure/password protected access to a file in Ubuntu 22.04
I have just recently installed Ubuntu 22.04 on my computer, and I don't know much about Linux. I have a file that I'm trying to secure (only accessible by password, for example)
Does anybody know how ...
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1
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100
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Block access by Geo location
I'm wondering if it's possible to block access based on location, as many hackers and ransomware attacks in recent years came from Russia or Belarus etc.
I dont want my vps accessed by those ...
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236
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HTTP request host header using netcat (nc)
How to use netcat (nc) to set host header in a HTTP request?
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With the release of Ubuntu Pro, Laravel Forge provisioned servers are left vulnerable
Since Canonical released Ubuntu Pro this year, they are now withholding some security patches for many common packages, including some that are included on Laravel Forge provisioned servers.
I use AWS ...
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0
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120
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Problem in tang/clevis (NBDE) Setup
I am trying to have NBDE on Ubunutu LTS 22.04.1 . basically i want my compute-1 node to auto decrypt on boot when it's able to ping controller (tang server) node. the problem is i encrypted every ...
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Compromised Ubuntu? Weird unauthorised iso file downloads and download attempts
I noticed 2 failed attempts at downloading an iso file in my Downloads, that were attempted without my knowing. It happened while I was using the computer (attempt time 10:06, screenshot 1). The ...
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is it possible to install kerberos for different distros?
I want to install kerberos on AlmaLinux as server to manage ubuntu clients.
is this possible? i read somewhere that in order to use kerberos, "Both devices have the same operating system".
...
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1
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101
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File Access dates changed unexpectedly. Metadata crawler?
Is it usual for file access dates (read dates) to change without human interaction? Which applies for all files under /home/myusername/ if I see that correctly but not for system files.
My personal ...
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1
answer
108
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DISA-STIG compliance script for personal use
I saw Ubuntu Security Guide and various compliances scripts for hardening. I've never used any of these scripts before and was curious to see.
I chose the DISA-STIG script. After a reboot a strange ...
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1
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What's the point of verifying downloads against the sha256 hash? [duplicate]
Just out of curiosity - Ubuntu and other Linux distributions tell users to verify downloaded .ISOs against the SHA256 hash of the .ISO.
1 - Since the SHA256 hash value is hosted on the same website as ...
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106
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Security update that doesnt look right
An update for Ubuntu is showing this:
Samba core libraries:
* SECURITY UPDATE: Multiple regressions (LP: #2003867) (LP: #2003891)
- debian/patches/series: disable all security fixes from the ...
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Trace IP address for a Tox user throw a bootstarp
I Try to get the IP of a Tox-friend.
I used wireshark, to figure out wich DHT bootstap is used to connect us (from this list https://nodes.tox.chat/).
I analyze packets from and to the DHT and i didn'...
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1
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Why does the security.ubuntu.com repository exist?
Looking at the contends of the /etc/apt/sources.list file two repositories are listed:
archive.ubuntu.com and security.ubuntu.com
At first I thought that the security repository only contains security ...
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How to patch CVE-2022-26373 for Ubuntu 20.04 gcp-5.13 and gcp-5.15?
Is there any patch/upgrade available for CVE-2022-26373, specifically for Ubuntu 20.04 gcp-5.13 and gcp-5.15?
From https://ubuntu.com/security/CVE-2022-26373:
Package
Status
linux-gcp-5.13
Ignored (...
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I am looking for a good domain block filter
Is there a domain block filter similar to ufdbguard?
UfdbGuard has not been updated for a long time and will not work properly on Ubuntu 22.04.
Do you have any good suggestions?
Best Regards!
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fips diables wireless interface
I enable fips through https://ubuntu.com/security/certifications/docs/fips-enablement, but after rebooting, the wireless interface disappears and mousepad gets disabled. Where can I re-enable them?
'...
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0
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109
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Unusual activity on my Ubuntu
I am running a device with Ubuntu installed, this device hasn’t been connected to the internet for few months. I have installed Ubuntu on a different device, then used a usb to transfer files between ...
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sshd banner exchange error messages
Starting yesterday, began seeing thousands of messages like this in the auth.log
sshd[3635916]: banner exchange: Connection from 202.142.184.68 port 24571: invalid format
Almost 17,000 occurrences of ...
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