Preface: Technology cannot fight against coronavirus in the moment.
Easter, commemorating the resurrection of Jesus from the dead.
Wish that human can managed to fight it all. Comparing with coronavirus. The vulnerability in computer system looks easy resolve.

Security focus – Juniper Network product:

A privilege escalation vulnerability in Juniper Networks Junos OS devices configured with dual Routing Engines (RE), Virtual Chassis (VC) or high-availability cluster may allow a local authenticated low-privileged user with access to the shell to perform unauthorized configuration modification. This issue does not affect Junos OS device with single RE or stand-alone configuration.

My observation: Refer to attach diagram, below is the information for supplement.

Fundamental
/bin/sh is an executable representing the system shell. Actually, it is usually implemented as a symbolic link pointing to the executable for whichever shell is the system shell.
Since it is a bash file so commands inside it will get executed, and if we execute the file as root, then all the commands inside it will also get executed as root. So, let’s take advantage of that and append /bin/bash -i to the file. This will execute bash as root, which in turn will open the root shell.

Official announcement of this matter (JunOS vulnerability) – https://kb.juniper.net/InfoCenter/index?page=content&id=JSA11010&cat=SIRT_1&actp=LIST

Preface: Dockerized Vesta Control Panel aka vestacp. You can download vesta source code and modify it the way you want. You are totally free to do it so to Vesta is licensed under GPL

Background: You are able to install and configure VestaCP on an Alibaba Cloud Elastic Compute Service (ECS) instance with CentOS 7

Vulnerability details: The proof of concept by Metasploit that a Low privileged authenticated users can execute arbitrary commands under the context of the root user. An authenticated attacker with a low privileges can inject a payload in the file name starts with dot. During the user backup process, this file name will be evaluated by the v-user-backup bash scripts. As result of that backup process, when an attacker try to list existing backups injected payload will be executed.

Remedy – Remedy looks not release yet, it is suggested to focus in official announcement. https://forum.vestacp.com/viewforum.php?f=25

Preface: According on 2020 market statistic, FireFox market share only 9.25%. But Chrome has 68.11% coverage. However I like FireFox.

How Firefox’s memory allocator works?

Firefox uses a memory allocator called moz jemalloc. There are two properties which focus by cyber security expert so far!

[PSJ] – In essence, a chunk is broken into several runs.

– Each run holds regions of a specific size. [TSOF]

– The feature of jemalloc is that it operates in a last-in-first-out (LIFO) manner, a free followed by a garbage collection and a subsequent allocation request for the same size, most likely ends up in the freed region.

Vulnerability details: CVE-2020-6819 is a use-after-free vulnerability due to a race condition when the nsDocShell destructor is running. CVE-2020-6820 is a use-after-free vulnerability due to a race condition in the ReadableStream class, which is used to read a stream of data.

Official announcement – https://www.mozilla.org/en-US/security/advisories/mfsa2020-11/

Preface: Maybe the software vendor didn’t disclose it explicitly. But you will be interested review this concept.

Background: Adobe Creative Cloud is a set of applications and services from Adobe Inc. that gives subscribers access to a collection of software used for graphic design, video editing, web development, photography, along with a set of mobile applications and also some optional cloud services. The Creative Cloud desktop application is instralled automatically when you download your first Creative Cloud product. If you have Adobe Application Manager installed, it auto-updated to the Creative Cloud desktop application.

Vulnerability Details: Creative Cloud Desktop Application versions 4.6.1 and earlier have a using components with known vulnerabilities vulnerability. Successful exploitation could lead to arbitrary code execution. As the software vendor did not disclose details. The vulnerability is suspected to come from the synchronization feature. See whether the diagram can provides an hints to you.

Official Announcement – https://helpx.adobe.com/security/products/creative-cloud/apsb20-11.html

Preface: Make our life easy, just rename or disable it.

Background: Type 1 is a font format which came to market around 1984, together with PostScript and the Apple LaserWriter. Perhaps ATMFD.DLL was first built into Windows 2000. Through observation, this vulnerability was caught by Google project Zero in 2015. Over time, maybe someone has forgotten this. Therefore, the direct method is to disable it.

Impact: Stacks in computing architectures are regions of memory where data is added or removed in a last-in-first-out (LIFO) manner. In most modern computer systems, each thread has a reserved region of memory referred to as its stack. A specially-crafted font that is capable of operating on any data on the thread stack and has all the instructions (including arithmetic, logic, condition, and other instructions) in the Type 1 / Type 2 Charstring instruction set. Official announcement: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/ADV200006

Or quick and Dirty: Right-click C:\Windows\System32\atmfd.dll Properties | Security | Advanced | Owner, take ownership. Close dialogs, go back in and give yourself Full Control.

Preface: Cisco SD-WAN Solution Privilege Escalation Vulnerability. Sound dangerous but it can only conduct internally. If someone can make it happen. It can elevate privileges to root on the underlying operating system.

Details: Perhaps Cisco fans still remember that a vulnerability encountered on SDWAN on Jun 2019. I presumably there may be similarities to this matter. The official announcement said An attacker could exploit this vulnerability by sending a crafted request to an affected system. A successful exploit could allow the attacker to gain root-level privileges. The details happened on June 2019 shown as below:

Cisco official announcement – https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwpresc-ySJGvE9

Other than that perhaps you will be interested of other vulnerabilities found on SDWAN

Buffer overflow – https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwanbo-QKcABnS2

Command Injection – https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwclici-cvrQpH9v

Preface: ThinPrint technology offload the print burden on all virtual and physical desktops, and keeps all client hardware free of printer drivers.

Background: VMware Workstation is a type 2 hypervisor. Type 2 hypervisors are essentially treated as applications because they install on top of a server’s OS. If the host gets cracked, the hypervisor gets cracked. If the hypervisor gets cracked, it depends on the host will have vulnerability let hacker to be use. From technical point of view, it is difficult but it may possible.

Vulnerability details: Linux Guest VMs running on VMware Workstation (15.x before 15.5.2) and Fusion (11.x before 11.5.2) contain a local privilege escalation vulnerability due to improper file permissions in Cortado Thinprint. Local attackers with non-administrative access to a Linux guest VM with virtual printing enabled may exploit this issue to elevate their privileges to root on the same guest VM. For the details of attack. Please refer to diagram.

Official announcement – https://www.vmware.com/security/advisories/VMSA-2020-0004.html

Preface: Microsoft has released a security advisory to address a remote code execution vulnerability (CVE-2020-0796) in Microsoft Server Message Block 3.1.1 (SMBv3) on 11th Mar 2020.

Vulnerability details: A remote attacker can exploit this vulnerability (CVE-2020-0796) to take control of an affected system. A “potentially wormable” vulnerability exists in SMBv3 and specifically the compression. Citrix already hints that SMB3 has design limitation occurs (see below):

CIFS compression—CIFS connections are compressed automatically whenever they meet the requirements for CIFS protocol acceleration. In addition, SMB3 connections are compressed when unsigned and unsealed.

Why is it dangerous? SMB Signing is a feature through which communications using SMB can be digitally signed at the packet level. Digitally signing the packets enables the recipient of the packets to confirm their point of origination and their authenticity. This security mechanism in the SMB protocol helps avoid issues like tampering of packets and “man in the middle” attacks.

Remedy solution by Microsoft – https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/adv200005