Do Not Preset known_hosts for the SSH Service

knownhosts stores the public keys of the computers that the host has accessed. After a user successfully logs in to another computer, the public key information is automatically saved in $HOME/.ssh/knownhosts. When the same computer is accessed next time, its public key is verified. If the...

Do Not Start the debug-shell Service

The debug-shell service is used to locate faults that occur during system boot. This service is installed with systemd. The debug-shell service requires no authentication, that is, attackers can access the root shell by simply pressing Ctrl+Alt+F9 during systemd startup when the OS is booting. Th...

Ensure That the su Command Inherits the User Environment Variables Without Escalating Privileges

The su command enables a common user to have the permissions of the superuser or other users. It is often used for switching the user from a common user to the root user. The su command provides a convenient way for users to change their identities. However, if the su command is run without...

Do Not Preset authorized_keys for the SSH Service

authorizedkeys specifies the public key of the remote host. You can store the public key in the $HOME/.ssh/authorizedkeys file in the home directory for public key authentication. Then you can directly log in to the system. If authorizedkeys is preset in the system and public and private key...

Do Not Install the rsync Service

The rsync service can synchronize data between servers or between local drive partitions. However, information leakage risks exist because rsync uses non-encrypted transmission protocols. If the rsync service is enabled and data is transmitted between servers over the network, attackers can...

Ensure That the su Command Is Restricted

The su command enables a common user to have the permissions of the superuser or other users. It is often used for switching the user from a common user to the root user. The su command provides a convenient way for users to change their identities. However, if the su command is run without...

Do Not Use X11 Forwarding

The X11 forwarding function of SSH allows the GUI program of the remote host to be executed on the local host. If the X11 forwarding function is enabled, the attack surface is expanded and other users on the X11 server may attack the local host. If the function is not required in the service...

Configure a Proper Number of Concurrent Sessions Allowed for a Single SSH Connection

SSH allows a client that supports multiplexing to establish multiple sessions based on a network connection. MaxSessions limits the number of concurrent SSH sessions that can be established for each network connection. This prevents system resources from being occupied by a single connection or a...

Do Not Configure Deprecated Options for the SSH Service

Currently, the SSH service communication protocols are classified into the first generation and the second generation. The configuration options of the SSH service of different versions are incompatible. In addition, the configuration options of some earlier versions are deprecated in the new...

Avoid Using the root User to Access the System Locally

Users with the root permission can access all Linux resources. If the root user is used to log in to the Linux OS to perform operations, there are many potential security risks. To avoid the risks, do not use the root user to log in to the Linux OS. If necessary, indirectly use the root user...

Ensure That a Common User Cannot Use pkexec for Privilege Escalation

The pkexec command enables a common user to have the permissions of the superuser or other users. After the authentication is successful, the common user runs the corresponding program with the permissions of the superuser. The pkexec command provides a convenient way for users to change their...

Ensure That the umask Value Is Correct

The umask value is the mask for default file or directory permissions. When a file or directory is created, its default permission is set to 777 minus the umask value. For a file, its execute permission is also removed. If the umask value is set improperly, the permission of new files may be too...

Linux Distros Unpatched Vulnerability : CVE-2021-33630

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - NULL Pointer Dereference vulnerability in openEuler kernel on Linux network modules allows Pointer Manipulation. This vulnerability is associated with program...

Linux Distros Unpatched Vulnerability : CVE-2024-24898

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Exposure of Sensitive Information to an Unauthorized Actor vulnerability in openEuler kernel on Linux allows Resource Leak Exposure. This vulnerability is...

Linux Distros Unpatched Vulnerability : CVE-2024-24891

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Exposure of Sensitive Information to an Unauthorized Actor vulnerability in openEuler kernel on Linux allows Resource Leak Exposure. This vulnerability is...

Astra Linux – Vulnerability in giflib

A heap-based buffer overflow vulnerability exists in the openEuler giflib component on Linux. This vulnerability is associated with the program file gif2rgb.C. This issue affects giflib versions up to 5.2.2...

CVE-2021-33633

Improper Neutralization of Special Elements used in an OS Command 'OS Command Injection' vulnerability in openEuler aops-ceres on Linux allows Command Injection. This vulnerability is associated with program files ceres/function/util.Py. This issue affects aops-ceres: from 1.3.0 through 1.4.1...

Ensure That the Password Protection Is Configured for GRUB

GRUB is the default bootloader of Linux. The bootloader can set the startup mode of the system. By setting the GRUB password, you can prevent attackers from modifying the GRUB setting to enter the single-user mode. If the GRUB password is not set, attackers can easily access the GRUB editing menu...

Ensure That the Password Validity Is Set Correctly

If a password is not changed for a long time, the password is vulnerable to brute force cracking, which compromises system security. If the password validity period is set too short, the password needs to be changed frequently, increasing management costs. In addition, users may fail to log in...

Ensure That a User Has Its Own Home Directory

Each user must have its own home directory for storing user-related data. The owner of the home directory must be the user. If the owner of the home directory is not the user, the user cannot read or write the home directory, or the user data stored in the home directory can be read or tampered...