Symbolic Link Vulnerabilities
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Configuring UNIX-Specific Settings: Creating Symbolic Links : Snap
Configuring UNIX-specific settings: Creating symbolic links Snap Creator Framework NetApp September 23, 2021 This PDF was generated from https://docs.netapp.com/us-en/snap-creator- framework/installation/task_creating_symbolic_links_for_domino_plug_in_on_linux_and_solaris_hosts.ht ml on September 23, 2021. Always check docs.netapp.com for the latest. Table of Contents Configuring UNIX-specific settings: Creating symbolic links . 1 Creating symbolic links for the Domino plug-in on Linux and Solaris hosts. 1 Creating symbolic links for the Domino plug-in on AIX hosts. 2 Configuring UNIX-specific settings: Creating symbolic links If you are going to install the Snap Creator Agent on a UNIX operating system (AIX, Linux, and Solaris), for the IBM Domino plug-in to work properly, three symbolic links (symlinks) must be created to link to Domino’s shared object files. Installation procedures vary slightly depending on the operating system. Refer to the appropriate procedure for your operating system. Domino does not support the HP-UX operating system. Creating symbolic links for the Domino plug-in on Linux and Solaris hosts You need to perform this procedure if you want to create symbolic links for the Domino plug-in on Linux and Solaris hosts. You should not copy and paste commands directly from this document; errors (such as incorrectly transferred characters caused by line breaks and hard returns) might result. Copy and paste the commands into a text editor, verify the commands, and then enter them in the CLI console. The paths provided in the following steps refer to the 32-bit systems; 64-bit systems must create simlinks to /usr/lib64 instead of /usr/lib. -
LS-09EN. OS Permissions. SUID/SGID/Sticky. Extended Attributes
Operating Systems LS-09. OS Permissions. SUID/SGID/Sticky. Extended Attributes. Operating System Concepts 1.1 ys©2019 Linux/UNIX Security Basics Agenda ! UID ! GID ! Superuser ! File Permissions ! Umask ! RUID/EUID, RGID/EGID ! SUID, SGID, Sticky bits ! File Extended Attributes ! Mount/umount ! Windows Permissions ! File Systems Restriction Operating System Concepts 1.2 ys©2019 Domain Implementation in Linux/UNIX ! Two types domain (subjects) groups ! User Domains = User ID (UID>0) or User Group ID (GID>0) ! Superuser Domains = Root ID (UID=0) or Root Group ID (root can do everything, GID=0) ! Domain switch accomplished via file system. ! Each file has associated with it a domain bit (SetUID bit = SUID bit). ! When file is executed and SUID=on, then Effective UID is set to Owner of the file being executed. When execution completes Efective UID is reset to Real UID. ! Each subject (process) and object (file, socket,etc) has a 16-bit UID. ! Each object also has a 16-bit GID and each subject has one or more GIDs. ! Objects have access control lists that specify read, write, and execute permissions for user, group, and world. Operating System Concepts 1.3 ys©2019 Subjects and Objects Subjects = processes Objects = files (regular, directory, (Effective UID, EGID) devices /dev, ram /proc) RUID (EUID) Owner permissions (UID) RGID-main (EGID) Group Owner permissions (GID) +RGID-list Others RUID, RGID Others ID permissions Operating System Concepts 1.4 ys©2019 The Superuser (root) • Almost every Unix system comes with a special user in the /etc/passwd file with a UID=0. This user is known as the superuser and is normally given the username root. -
Linux Filesystem Hierarchy Chapter 1
Linux Filesystem Hierarchy Chapter 1. Linux Filesystem Hierarchy 1.1. Foreward When migrating from another operating system such as Microsoft Windows to another; one thing that will profoundly affect the end user greatly will be the differences between the filesystems. What are filesystems? A filesystem is the methods and data structures that an operating system uses to keep track of files on a disk or partition; that is, the way the files are organized on the disk. The word is also used to refer to a partition or disk that is used to store the files or the type of the filesystem. Thus, one might say I have two filesystems meaning one has two partitions on which one stores files, or that one is using the extended filesystem, meaning the type of the filesystem. The difference between a disk or partition and the filesystem it contains is important. A few programs (including, reasonably enough, programs that create filesystems) operate directly on the raw sectors of a disk or partition; if there is an existing file system there it will be destroyed or seriously corrupted. Most programs operate on a filesystem, and therefore won't work on a partition that doesn't contain one (or that contains one of the wrong type). Before a partition or disk can be used as a filesystem, it needs to be initialized, and the bookkeeping data structures need to be written to the disk. This process is called making a filesystem. Most UNIX filesystem types have a similar general structure, although the exact details vary quite a bit. -
Mac Keyboard Shortcuts Cut, Copy, Paste, and Other Common Shortcuts
Mac keyboard shortcuts By pressing a combination of keys, you can do things that normally need a mouse, trackpad, or other input device. To use a keyboard shortcut, hold down one or more modifier keys while pressing the last key of the shortcut. For example, to use the shortcut Command-C (copy), hold down Command, press C, then release both keys. Mac menus and keyboards often use symbols for certain keys, including the modifier keys: Command ⌘ Option ⌥ Caps Lock ⇪ Shift ⇧ Control ⌃ Fn If you're using a keyboard made for Windows PCs, use the Alt key instead of Option, and the Windows logo key instead of Command. Some Mac keyboards and shortcuts use special keys in the top row, which include icons for volume, display brightness, and other functions. Press the icon key to perform that function, or combine it with the Fn key to use it as an F1, F2, F3, or other standard function key. To learn more shortcuts, check the menus of the app you're using. Every app can have its own shortcuts, and shortcuts that work in one app may not work in another. Cut, copy, paste, and other common shortcuts Shortcut Description Command-X Cut: Remove the selected item and copy it to the Clipboard. Command-C Copy the selected item to the Clipboard. This also works for files in the Finder. Command-V Paste the contents of the Clipboard into the current document or app. This also works for files in the Finder. Command-Z Undo the previous command. You can then press Command-Shift-Z to Redo, reversing the undo command. -
Powershell Integration with Vmware View 5.0
PowerShell Integration with VMware® View™ 5.0 TECHNICAL WHITE PAPER PowerShell Integration with VMware View 5.0 Table of Contents Introduction . 3 VMware View. 3 Windows PowerShell . 3 Architecture . 4 Cmdlet dll. 4 Communication with Broker . 4 VMware View PowerCLI Integration . 5 VMware View PowerCLI Prerequisites . 5 Using VMware View PowerCLI . 5 VMware View PowerCLI cmdlets . 6 vSphere PowerCLI Integration . 7 Examples of VMware View PowerCLI and VMware vSphere PowerCLI Integration . 7 Passing VMs from Get-VM to VMware View PowerCLI cmdlets . 7 Registering a vCenter Server . .. 7 Using Other VMware vSphere Objects . 7 Advanced Usage . 7 Integrating VMware View PowerCLI into Your Own Scripts . 8 Scheduling PowerShell Scripts . 8 Workflow with VMware View PowerCLI and VMware vSphere PowerCLI . 9 Sample Scripts . 10 Add or Remove Datastores in Automatic Pools . 10 Add or Remove Virtual Machines . 11 Inventory Path Manipulation . 15 Poll Pool Usage . 16 Basic Troubleshooting . 18 About the Authors . 18 TECHNICAL WHITE PAPER / 2 PowerShell Integration with VMware View 5.0 Introduction VMware View VMware® View™ is a best-in-class enterprise desktop virtualization platform. VMware View separates the personal desktop environment from the physical system by moving desktops to a datacenter, where users can access them using a client-server computing model. VMware View delivers a rich set of features required for any enterprise deployment by providing a robust platform for hosting virtual desktops from VMware vSphere™. Windows PowerShell Windows PowerShell is Microsoft’s command line shell and scripting language. PowerShell is built on the Microsoft .NET Framework and helps in system administration. By providing full access to COM (Component Object Model) and WMI (Windows Management Instrumentation), PowerShell enables administrators to perform administrative tasks on both local and remote Windows systems. -
Where Do You Want to Go Today? Escalating
Where Do You Want to Go Today? ∗ Escalating Privileges by Pathname Manipulation Suresh Chari Shai Halevi Wietse Venema IBM T.J. Watson Research Center, Hawthorne, New York, USA Abstract 1. Introduction We analyze filename-based privilege escalation attacks, In this work we take another look at the problem of where an attacker creates filesystem links, thereby “trick- privilege escalation via manipulation of filesystem names. ing” a victim program into opening unintended files. Historically, attention has focused on attacks against priv- We develop primitives for a POSIX environment, provid- ileged processes that open files in directories that are ing assurance that files in “safe directories” (such as writable by an attacker. One classical example is email /etc/passwd) cannot be opened by looking up a file by delivery in the UNIX environment (e.g., [9]). Here, an “unsafe pathname” (such as a pathname that resolves the mail-delivery directory (e.g., /var/mail) is often through a symbolic link in a world-writable directory). In group or world writable. An adversarial user may use today's UNIX systems, solutions to this problem are typ- its write permission to create a hard link or symlink at ically built into (some) applications and use application- /var/mail/root that resolves to /etc/passwd. A specific knowledge about (un)safety of certain directories. simple-minded mail-delivery program that appends mail to In contrast, we seek solutions that can be implemented in the file /var/mail/root can have disastrous implica- the filesystem itself (or a library on top of it), thus providing tions for system security. -
File Permissions Do Not Restrict Root
Filesystem Security 1 General Principles • Files and folders are managed • A file handle provides an by the operating system opaque identifier for a • Applications, including shells, file/folder access files through an API • File operations • Access control entry (ACE) – Open file: returns file handle – Allow/deny a certain type of – Read/write/execute file access to a file/folder by – Close file: invalidates file user/group handle • Access control list (ACL) • Hierarchical file organization – Collection of ACEs for a – Tree (Windows) file/folder – DAG (Linux) 2 Discretionary Access Control (DAC) • Users can protect what they own – The owner may grant access to others – The owner may define the type of access (read/write/execute) given to others • DAC is the standard model used in operating systems • Mandatory Access Control (MAC) – Alternative model not covered in this lecture – Multiple levels of security for users and documents – Read down and write up principles 3 Closed vs. Open Policy Closed policy Open Policy – Also called “default secure” • Deny Tom read access to “foo” • Give Tom read access to “foo” • Deny Bob r/w access to “bar” • Give Bob r/w access to “bar • Tom: I would like to read “foo” • Tom: I would like to read “foo” – Access denied – Access allowed • Tom: I would like to read “bar” • Tom: I would like to read “bar” – Access allowed – Access denied 4 Closed Policy with Negative Authorizations and Deny Priority • Give Tom r/w access to “bar” • Deny Tom write access to “bar” • Tom: I would like to read “bar” – Access -
Filesystem Hierarchy Standard
Filesystem Hierarchy Standard LSB Workgroup, The Linux Foundation Filesystem Hierarchy Standard LSB Workgroup, The Linux Foundation Version 3.0 Publication date March 19, 2015 Copyright © 2015 The Linux Foundation Copyright © 1994-2004 Daniel Quinlan Copyright © 2001-2004 Paul 'Rusty' Russell Copyright © 2003-2004 Christopher Yeoh Abstract This standard consists of a set of requirements and guidelines for file and directory placement under UNIX-like operating systems. The guidelines are intended to support interoperability of applications, system administration tools, development tools, and scripts as well as greater uniformity of documentation for these systems. All trademarks and copyrights are owned by their owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Permission is granted to make and distribute verbatim copies of this standard provided the copyright and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this standard under the conditions for verbatim copying, provided also that the title page is labeled as modified including a reference to the original standard, provided that information on retrieving the original standard is included, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this standard into another language, under the above conditions for modified versions, except that this permission notice may be stated in a translation approved by the copyright holder. Dedication This release is dedicated to the memory of Christopher Yeoh, a long-time friend and colleague, and one of the original editors of the FHS. -
Autodesk Alias 2016 Hardware Qualification
Autodesk Alias 2016 Hardware Qualification Updated June 1, 2015 Windows Mac OSX Build Information Products Platform Version Software Date Build Number • Autodesk AutoStudio • Autodesk Alias Surface 64-bit 2016 March 6, 2015 201503061129-441529 • Autodesk Alias Design Supported Operating Systems and CPU Platforms Operating System CPU Platform Windows 7 SP1 Intel Xeon (Enterprise, Ultimate or Professional) 64-bit Intel Core AMD Opteron Windows 8.0 or 8.1 Intel Xeon (Enterprise or Professional) 64-bit Intel Core AMD Opteron Important Notes • Alias AutoStudio, Automotive, Surface and Design fully support 64-bit environments. Running the 64-bit native version requires Windows 8 or 8.1 64-bit or Windows 7 64-bit operating system. • Certain 3rd party software may alter the processor affinity settings, affecting multi-cpu systems running Alias.exe and its spawned processes. To check the affinity setting, right-click on the Alias.exe process inside the Windows Task Manager and select Set Affinity... ensure that all available CPUs are enabled. • Alias or its component programs may not launch successfully depending on your Windows security settings. If this occurs, you may either unblock the program via the Windows Firewall Security Alert dialog, or add it as an Exception in the Exceptions Tab in the Windows Firewall dialog box. For more information, please see the Microsoft Update. Similar configurations are necessary for any third party firewall software, Please Read • It may be possible to successfully use Alias for Windows with a non-qualified configuration, however, Support and Maintenance programs will be subject to the Autodesk Support services guidelines. • The configurations shown are subject to change, and additional qualified configurations may be added after qualification testing has been carried out. -
An Incremental Path Towards a Safer OS Kernel
An Incremental Path Towards a Safer OS Kernel Jialin Li Samantha Miller Danyang Zhuo University of Washington University of Washington Duke University Ang Chen Jon Howell Thomas Anderson Rice University VMware Research University of Washington LoC Abstract Incremental Progress Tens of Linux Safe Linux Linux has become the de-facto operating system of our age, Millions FreeBSD but its vulnerabilities are a constant threat to service availabil- Hundreds of Singularity ity, user privacy, and data integrity. While one might scrap Thousands Biscuit Linux and start over, the cost of that would be prohibitive due Theseus Thousands RedLeaf seL4 to Linux’s ubiquitous deployment. In this paper, we propose Hyperkernel Safety an alternative, incremental route to a safer Linux through No Type Ownership Functional proper modularization and gradual replacement module by Guarantees Safety Safety Verification module. We lay out the research challenges and potential Figure 1: Our vision and the current state of systems. solutions for this route, and discuss the open questions ahead. security vulnerabilities are reported each year, and lifetime CCS Concepts analysis suggests that the new code added this year has intro- duced tens of thousands of more bugs. ! • Software and its engineering Software verification; While operating systems are far from the only source of se- ! • Computer systems organization Reliability. curity vulnerabilities, it is hard to envision building trustwor- Keywords thy computer systems without addressing operating system correctness. kernel safety, verified systems, reliable systems One attractive option is to scrap Linux and start over. Many ACM Reference Format: past works focus on building more secure and correct op- Jialin Li, Samantha Miller, Danyang Zhuo, Ang Chen, Jon Howell, erating systems from the ground up: ones based on strong and Thomas Anderson. -
Filesystem Hierarchy Standard
Filesystem Hierarchy Standard Filesystem Hierarchy Standard Group Edited by Rusty Russell Daniel Quinlan Filesystem Hierarchy Standard by Filesystem Hierarchy Standard Group Edited by Rusty Russell and Daniel Quinlan Published November 4 2003 Copyright © 1994-2003 Daniel Quinlan Copyright © 2001-2003 Paul ’Rusty’ Russell Copyright © 2003 Christopher Yeoh This standard consists of a set of requirements and guidelines for file and directory placement under UNIX-like operating systems. The guidelines are intended to support interoperability of applications, system administration tools, development tools, and scripts as well as greater uniformity of documentation for these systems. All trademarks and copyrights are owned by their owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark. Permission is granted to make and distribute verbatim copies of this standard provided the copyright and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this standard under the conditions for verbatim copying, provided also that the title page is labeled as modified including a reference to the original standard, provided that information on retrieving the original standard is included, and provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Permission is granted to copy and distribute translations of this standard into another language, under the above conditions for modified versions, except that this permission notice may be stated in a translation approved by the copyright holder. Table of Contents 1. Introduction........................................................................................................................................................1 1.1. -
Simple File System (SFS) Format
Simple File System (SFS) Format Version SFS-V00.01 The SFS is a simple file system format optimized for writing and for low overhead.. The advantages of this format are: • Event navigation is possible using simple content-independent file system like functions. • Very low overhead. No loss due to block size granularity • Entire valid file system can be created by appending content On the other hand, random access directory navigation is rather slow because there is no built-in indexing or directory hierarchy. For a 500MB file system containing files with 5k bytes this represents an initial search overhead of ~1-2 sec (~100,000 seeks). SFS Structure The structure of a SFS file is as follows VolumeSpec Head File1 File1 Binary Data File2 File2 Binary Data ... ... Tail VolumeSpec: This is simply a 12 byte character string representing filesystem version. For example: “SFS V00.01” Head: This is a short header record. The byte order only applies to the time field of this record. type = “HEAD” byte_order = 0x04030201 time File: The File records are a variable length record containing information about a file. type = “FILE” byte_order = 0x04030201 Sz head_sz attr reserved name.... name (continued).... “byte_order” corresponds only to this header. The endiness of the data is undefined by SFS “sz” corresponds to the datafile size. This may be any number, but the file itself will be padded to take up a multiple of 4 bytes “head_sz” this must be a multiple of 4 “attr” SFS_ATTR_INVALID: file deleted SFS_ATTR_PUSHDIR: push current path to path stack SFS_ATTR_POPDIR: pop current path from path stack SFS_ATTR_NOCD: this record doesn’t reset the basedir “name” the name of the file.