Category Archives: Potential Risk of CVE

Closer look: CVE-2019-1162 Windows ALPC Elevation of Privilege Vulnerability

Preface: ALPC (Advanced/Asynchronous Local Procedure Call) is a C/S model technology developed by Microsoft to replace LPC for native RPC.

Vulnerability details: Tasks created by the Task Scheduler will create the folder and file in “c:\windows\system32\ tasks”. This function original to be designed to write the discretionary access control list of the task in this place. For some reason, it also checks if the .job file exists under c:\ windows \ tasks and tries to set the DACL

Since users belonging to the guest group, can create files in this folder, we can simply create a hard link to another file (we only need to read access). Due to the hard link, we can let the task scheduler write any DACL (see the second parameter of SchRpcSetSecurity) to the file of our choice. Therefore, any file we read is accessed as a user, and the system has write DACL permissions, we can go to full control and overwrite it.

Vendor announcement : https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1162

THE GREATER THE POWER OF THE COUNTRY, THE STRONGER THE SUPERCOMPUTER.

Summit, launched in 2018, delivers 8 times the computational performance of Titan’s 18,688 nodes, using only 4,608 nodes. Summit still carry the flags tell the world that he keep the fast run record.

Over the past decade, Linux Clusters founded and starting the competition with mainframe computer. The most famous IBM crossbar switch encounter doubt to technical world. Does he better than Linux Clusters? Crossbar – The processors are connected with non-internally blocking crossbar switch and communicate with each other via global interleaved memory.

The record shown on the diagram, even though the supercomputer CPU core increase 4 times compare to submit. But it do not have significant growth. Perhaps you may feeling that the bottleneck given from CPU. My personal comment is that crossbar coexists CPU and I/O direct way. Linux cluster form virtual matrix hoop up. But the design limitation is the server hardware instead of CPU. We keep our eye open to see who is the winner on next round? A crossbar switch, as part of a crossbar topology, channels data or signals between two different points in a network.

Remark: The crossbar setup is a matrix where each crossbar switch runs between two points, in a design that is intended to hook up each part of an architecture to every other part.

CVE-2019-10099 Apache Spark Unencrypted Data Vulnerability Aug 2019

Background: Apache Spark is the tailor made for big data industry.Spark’s advanced acyclic processing engine can operating as a stand-alone mode or a cloud service.

Synopsis: Spark supports encrypting temporary data written to local disks. This covers shuffle files, shuffle spills and data blocks stored on disk (for both caching and broadcast variables). It does not cover encrypting output data generated by applications with APIs such as saveAsHadoopFile or saveAsTable. It also may not cover temporary files created explicitly by the user.

Vulnerability details: The vulnerability is due to a cryptographic issue in the affected software that allows user data to be written to the local disk unencrypted in certain situations, even if the spark.io.encryption.enabled property is set to true.

Security focus: This vulnerability did not category as critical. But the level of risk will be depends on the system architecture and classification level of data. For instance, it is a machine learning function and install on top of public cloud computer farm. If this is the case, a serious access restriction control to Spark infrastructure area must be apply.

Remedy: Apache has released software updates at the following link – https://spark.apache.org/downloads.html

CVE-2019-14544 Gogs Permission Checking vulnerability Aug 2019

Preface: If you are not yet ready to share your project on GitHub. You can host your own Private GitHub. It is Gogs.

Product background: The goal of Gogs is to make the easiest, fastest, and most painless way of setting up a self-hosted Git service. So all the design concept, program code and perhaps intellectual properties all keep in this place. Since the intension is not go for public and therefore it will be installed on private cloud or a single machine.

Vulnerability details: A design defect found in source code file (routes/api/v1/api.go). The impact causes affected software does not properly perform permission checks for routes.
Since there is no preventive control and therefore an attacker could exploit this vulnerability to perform unauthorized actions on a targeted system. Should you have interested of this issue, see top right hand side of the diagram. You will find part of the enhancement features. Perhaps you will speculate what is the actual problem.

Remedy – See url https://github.com/gogs/gogs/blob/master/routes/api/v1/api.go

CVE-2019-11042 PHP flaw form a way to read past the allocated buffer. This may lead to information disclosure or crash. Aug 2019

Preface: We knew Python programming language has large footprint in IoT world. Have you heard PHPoC (PHP on Chip) – a programming language and an IoT hardware platform? So, PHP programming language still have survival space.

Background: The EXIF headers tend to be present in JPEG/TIFF images generated by digital cameras. In order to read meta data generated by digital cameras , software application simply using the standard exif_read_data() function.

Vulnerability details: When PHP EXIF extension is parsing EXIF information from an image (e.g. via exif_read_data() function).
Such defect possible to supply it with data what will cause it to read past the allocated buffer and causes data leak.

Affected version: in PHP versions 7.1.x below 7.1.31, 7.2.x below 7.2.21 and 7.3.x below 7.3.8

How smart of the smartcity, depends on your vulnerability management (CVE-2019-14462 & CVE-2019-14463) Aug 2019

Preface: Why should we driven Artificial Intelligence like a maniac? We are mankind!

MODBUS techincal background: Modbus is a communication protocol developed by Modicon systems. In simple terms, it is a method used for transmitting information over serial lines between electronic devices. The device requesting the information is called the Modbus Master and the devices supplying information are Modbus Slaves.

Possible way – A string is properly null-terminated if a null terminator is present at or before the last element in the array. If a string lacks the terminating null character, the program may be tricked into reading or writing data outside the bounds of the array. A successful exploit could trigger an out-of-bounds read condition that the attacker could use to execute arbitrary code or cause a DoS condition.

Remedy – Official release updated to include important fixes: https://libmodbus.org/2019/stable-and-development-releases/

CVE-2019-1125 Status update 6th Aug 2019

Preface: GS register is used to differentiate between usermode and kernel mode range of address, after adding the relevant logical address component. The instruction swapgs is used to swap the GS register with the MSR values, and only in privileged mode this can be done.

Vulnerability details: CVE-2019-1125 was made public today or also referred to as the “SWAPGS” vulnerability as a new variant of Spectre V1 affecting Intel and AMD chips under Windows and Linux operation system. The SWAPGS vulnerability allows attackers to gain read access to privileged memory and builds off existing Spectre fixes. But AMD confirmed that its products are not vulnerable to this attack. Red Hat said it needs to update the Linux kernel to prevent SWAPGS vulnerabilities from affecting Intel and AMD chips.

Microsoft official announcement: https://portal.msrc.microsoft.com/en-us/security-guidance/advisory/CVE-2019-1125

Red Hat official announcement: https://access.redhat.com/articles/4329821

Das U-Boot Self-Referential DOS Partition Table Infinite Recursion Vulnerability Aug 2019

Vulnerability details: A crafted self-referential DOS partition table will cause all Das U-Boot versions through 2019.07-rc4 to infinitely recurse, causing the stack to grow infinitely and eventually either crash or overwrite other data.

Introduction: Das U-Boot a popular primary bootloader, it widely used in embedded devices to fetch data from different sources and run the next stage code.In the technology and computer markets, widely used to this bootloader is Linux Kernel. Meanwhile, it is commonly used by IoT. Kindle and ARM ChromeOS devices.

Remedy: Official remediation solution is disable DOS partition default sector for 512 because it’s not very common at all to use large numbers of partitions. Meanwhile set a maximum recursion level (refer to the parameter shown on attached diagram).

Please note that Das U-Boot has other vulnerabilities found. The CVE details shown as below:
CVE-2019-14192, CVE-2019-14193, CVE-2019-14194, CVE-2019-14195, CVE-2019-14196, CVE-2019-14197, CVE-2019-14198, CVE-2019-14199, CVE-2019-14200, CVE-2019-14201, CVE-2019-14202, CVE-2019-14203 and CVE-2019-14204

Above vulnerabilities could let attacker gain remote code execution at the U-Boot powered device when U-Boot is configured to use the network for fetching the next stage boot resources.

Official announcement on CVW-2019-13103https://lists.denx.de/pipermail/u-boot/2019-July/375512.html

iot devices security alert – cve-2019-14379 Aug 2019

What is Jackson Databind used for? Data Binding API is used to convert JSON to and from POJO (Plain Old Java Object) using property accessor or using annotations. It is of two type. Simple Data Binding – Converts JSON to and from Java Maps, Lists, Strings, Numbers, Booleans and null objects.

What is Ehcache? Ehcache is an open source, standards-based cache that boosts performance, offloads your database, and simplifies scalability.

Vulnerability details: A vulnerability in the FasterXML jackson-databind library could allow an unauthenticated remote attacker to execute arbitrary code on the target system. This defect exists because the SubTypeValidator.java source code file of the affected software incorrectly handles the default type when using Ehcache. An attacker could exploit this vulnerability by sending a request to submit a malicious input to the target system to execute arbitrary code.

Remedy: Update to jackson-databind release 2.9.9.2

VMware Releases Security Updates for Multiple Products – August 3, 2019

Preface: Are GPU vulnerable to hacker attacks?

Background: On virtual machines running VMware Fusion provides support for OpenGL 2.1 to support 3D accelerated desktops. It is not enabled by default on ESXi and is enabled by default on Workstation and Fusion.

Vulnerability details:

CVE-2019-5521 – may lead to information disclosure or may allow attackers with normal user privileges to create a denial-of-service condition on the host.

CVE-2019-5684 – This vulnerability can be exploited only if the host has an affected NVIDIA graphics driver. Successful exploitation of this issue may lead to code execution on the host.

Security Focus: Since no additional details provided by vendor. But believe that the possible way let hacker exploit CVE-2019-5521 design weakness is Perfect Timing Attacks (Please refer to photo). Apart from that the hacker can exploit out of bound read / write to bypass address space layout randomization (ASLR). So, be alerted!

Vendor announcement: please refer to the url – https://www.vmware.com/security/advisories/VMSA-2019-0012.html