Category Archives: Science

Science

Power outage in Spain and Portugal on caused by rare atmospheric phenomenon. So called Induced atmospheric vibration. (1st May 2025)

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Preface: MADRID/LISBON, April 28 (Reuters) – Power started returning to parts of the Iberian peninsula late on Monday after a huge outage brought most of Spain and Portugal to a standstill, grounding planes, halting public transport, and forcing hospitals to suspend routine operations.

Background: The recent widespread power outage in Spain, Portugal, and parts of southern France was indeed attributed to a rare atmospheric phenomenon. The initial reports suggested that “induced atmospheric vibration” might have been the cause. This term refers to oscillations in the power lines caused by extreme changes in temperature or air pressure, leading to synchronization failures in the electrical grid.

Technical focus: The term “induced atmospheric vibration” refers to oscillations in power lines caused by extreme atmospheric conditions, such as significant temperature changes or strong winds . These oscillations can affect the stability of the electrical grid.To simplify, imagine the power lines as giant coils. When the atmosphere changes rapidly, it can cause these coils to vibrate or oscillate. This vibration can lead to synchronization issues in the power grid, making it unstable and potentially causing outages.

Synchronization issues in the power grid often refer to the phase angle differences between the voltage waveforms of different parts of the grid. When the phase angles are not in sync, it means that the peaks and troughs of the voltage waveforms are not aligned, which can lead to instability in the grid.

In simpler terms, think of the power grid as a large orchestra. For the music (electricity) to flow smoothly, all the instruments (generators) need to play in harmony (synchronization). If one instrument is out of sync, it disrupts the harmony, causing issues.

The term “cos phi” (cosine of the phase angle) refers to the power factor, which is a measure of how effectively the electrical power is being used. When the phase angles are not aligned, the power factor deviates from its optimal value, leading to inefficiencies and potential disruptions

Headline News: Please refer to the link – https://www.reuters.com/world/europe/large-parts-spain-portugal-hit-by-power-outage-2025-04-28/

AI and ML, Potential Risk of CVE, Science, System

Similar to previously disclosed side-channel attacks. Manufacturer (AMD) response to researcher (30-03-2025)

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Preface: On 24th Oct, 2024, Researchers from Azure® Research, Microsoft® have provided to AMD a paper titled “Principled Microarchitectural Isolation on Cloud CPUs.” In their paper, the researchers describe a potential side-channel vulnerability on AMD CPUs. AMD believes that existing mitigation recommendations for prime and probe side-channel attacks remain applicable to the presented vulnerability.

Background: A two-bit saturating up-down counter is a type of counter used in computer architecture, particularly in branch prediction mechanisms. Here’s a brief overview:

  • Two-bit: The counter uses two bits, allowing it to represent four states (00, 01, 10, 11).
  • Up-down: The counter can increment (count up) or decrement (count down) based on the input signal.
  • Saturating: The counter does not wrap around when it reaches its maximum (11) or minimum (00) value. Instead, it stays at these values if further increments or decrements are attempted.
How It Works:
  1. States: The counter has four states: 00, 01, 10, and 11.
  2. Incrementing: If the counter is at 11 and receives an increment signal, it remains at 11. Similarly, if it is at 00 and receives a decrement signal, it stays at 00.
  3. Usage: These counters are often used in branch prediction to keep track of the history of branch outcomes and make predictions based on this history.

Ref: The pattern history table (PHT) branch architecture is an example of an architecture using two-bit saturating up-down counters. It contains a table of two-bit counters used to predict the direction for conditional branches.

About Branch History Leak:

Researchers from The Harbin Institute of Technology have shared with AMD a paper titled “Branch History LeakeR: Leveraging Branch History to Construct a New Side Channel-Theory and Practice” that demonstrates a side channel attack using the Global History Register (GHR).  The GHR is used to assist in conditional branch prediction. The researchers note that the GHR is shared between different security domains and may retain data after a security domain switch.  After a return to the user-space, the researchers were able to infer the direction of recently executed conditional branches.

Official announcement: Please refer to the link for details – https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7026.html

Potential Risk of CVE, Science

CVE-2025-29909: CryptoLib’s design weakness (19-03-2025)

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Preface: Human being life average 80 year old. Explorering space is a long time travel. So, it only relies on machine.

Even though exploring machine can relies on solar energy. In space there is a lot of uncertainty. For example, the  shock of meteorite. Furthemore, the spacecraft operates in a unique environment, the spacecraft’s power system must also be able to operate in zero gravity and vacuum conditions, and be able to withstand large amounts of radiation (most electronic equipment will not operate in such an environment). On our earth also have gravity seems not want human being leave our earth. Believed it or not, this is our destiny.

Background: CryptoLib is indeed used in space technology! It provides a C-based software implementation of the CCSDS Space Data Link Security Protocol (SDLS) and SDLS Extended Procedures (SDLS-EP) to secure communications between spacecraft flight software and ground stations. This library supports various encryption libraries and protocols, including Telecommand (TC), Telemetry (TM), and Advanced Orbiting Systems (AOS).

CryptoLib is designed to support smaller missions with stringent size, weight, and power constraints, making it a valuable tool for secure satellite communications.

Vulnerability details: CryptoLib provides a software-only solution using the CCSDS Space Data Link Security Protocol – Extended Procedures (SDLS-EP) to secure communications between a spacecraft running the core Flight System (cFS) and a ground station. In versions 1.3.3 and prior, a heap buffer overflow vulnerability in CryptoLib’s `Crypto_TC_ApplySecurity()` allows an attacker to craft a malicious TC frame that causes out-of-bounds memory writes. This can result in denial of service (DoS) or, under certain conditions, remote code execution (RCE). Any application or system that relies on CryptoLib for Telecommand (TC) processing and does not strictly validate incoming TC frames is at risk. This includes satellite ground stations or mission control software where attackers can inject malformed frames.

Official announcement: Please refer to the link for details – https://nvd.nist.gov/vuln/detail/CVE-2025-29909

Science, System

Python , have ever you though? (25-02-2025)

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Preface: Maintaining a satellite’s orbit involves a combination of precise calculations and regular adjustments. Here are the key factors:

  1. Velocity and Gravity: A satellite stays in orbit by balancing its velocity (speed in a straight line) with the gravitational pull of the Earth. The satellite must travel fast enough to counteract the pull of gravity, which keeps it in a stable orbit.
  2. Orbital Station-Keeping: This involves small adjustments using thrusters to correct any deviations in the satellite’s path. These maneuvers ensure the satellite remains in its designated orbit.
  3. Fuel Management: Satellites carry a limited amount of fuel for these adjustments. Efficient fuel management is crucial for prolonging the satellite’s operational life.
  4. Monitoring and Control: Ground stations continuously monitor satellites and send commands to perform necessary adjustments. This helps in maintaining the satellite’s orbit and addressing any potential issues.

Background: The PyEphem module provides highly precise data on the planets and our solar system. This module leverages an extremely robust C library that allows you to pinpoint planets, perform interplanetary calculations and discover more data than you’ll ever know what to do with.

Best practice: If you’re using PyEphem, it’s a good idea to keep your Python environment and libraries up to date and to check the module’s GitHub repository for any reported issues or updates.

AI and ML, IoT, Network (Protocol, Topology & Standard), Potential Risk of CVE, Science, System

CVE-2024-41009: bpf – Fix overrunning reservations in ringbuf (17th July 2024)

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Preface: Consumer and producer counters are put into separate pages to allow each position to be mapped with different permissions. This prevents a user-space application from modifying the position and ruining in-kernel tracking. The permissions of the pages depend on who is producing samples: user-space or the kernel. Starting from Linux 5.8, BPF provides a new BPF data structure (BPF map): BPF ring buffer (ringbuf). It is a multi-producer, single-consumer (MPSC) queue and can be safely shared across multiple CPUs simultaneously.

Background: The first core skill point is “BPF Hooks”, that is, where in the kernel can BPF programs be loaded. There are nearly 10 types of hooks in the current Linux kernel, as shown below:

kernel functions (kprobes)

userspace functions (uprobes)

system calls

fentry/fexit

Tracepoints

network devices (tc/xdp)

network routes

TCP congestion algorithms

sockets (data level)

Vulnerability details: For example, consider the creation of a BPF_MAP_TYPE_RINGBUF map with size of 0x4000. Next, the consumer_pos is modified to 0x3000 /before/ a call to bpf_ringbuf_reserve() is made. This will allocate a chunk A, which is in [0x0,0x3008], and the BPF program is able to edit [0x8,0x3008]. Now, lets allocate a chunk B with size 0x3000. This will succeed because consumer_pos was edited ahead of time to pass the `new_prod_pos – cons_pos > rb->mask` check. Chunk B will be in range [0x3008,0x6010], and the BPF program is able to edit [0x3010,0x6010]. Due to the ring buffer memory layout mentioned earlier, the ranges [0x0,0x4000] and [0x4000,0x8000] point to the same data pages. This means that chunk B at [0x4000,0x4008] is chunk A’s header. bpf_ringbuf_submit() / bpf_ringbuf_discard() use the header’s pg_off to then locate the bpf_ringbuf itself via bpf_ringbuf_restore_from_rec(). Once chunk B modified chunk A’s header, then bpf_ringbuf_commit() refers to the wrong page and could cause a crash.  

Official announcement: Please refer to the official announcement for details – https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=47416c852f2a04d348ea66ee451cbdcf8119f225

AI and ML, Application Development, Potential Risk of CVE, Science

CVE-2024-0102:  About NVIDIA® CUDA® Toolkit. If you remember, a similar incident happened in April of this year. Believe this is a weakness of similar designs. (11 July 2024)

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Preface: OpenAI revealed that the project cost $100 million, took 100 days, and used 25,000 NVIDIA A100 GPUs. Each server equipped with these GPUs uses approximately 6.5 kW, so an estimated 50 GWh of energy is consumed during training.

Background: Parallel processing is a method in computing of running two or more processors (CPUs) to handle separate parts of an overall task. Breaking up different parts of a task among multiple processors will help reduce the amount of time to run a program. GPUs render images more quickly than a CPU because of its parallel processing architecture, which allows it to perform multiple calculations across streams of data simultaneously. The CPU is the brain of the operation, responsible for giving instructions to the rest of the system, including the GPU(s).

NVIDIA CUDA provides a simple C/C++ based interface. The CUDA compiler leverages parallelism built into the CUDA programming model as it compiles your program into code.
CUDA is a parallel computing platform and programming interface model created by Nvidia for the development of software which is used by parallel processors. It serves as an alternative to running simulations on traditional CPUs.

Vulnerability details: NVIDIA CUDA Toolkit for all platforms contains a vulnerability in nvdisasm, where an attacker can cause an out-of-bounds read issue by deceiving a user into reading a malformed ELF file. A successful exploit of this vulnerability might lead to denial of service.

Official announcement: Please refer to the vendor announcement for details – https://nvidia.custhelp.com/app/answers/detail/a_id/5548

Potential Risk of CVE, Science, Under our observation

To be new or it was former: Rowhammer Attacks on AMD Zen-Based Platforms. So called ZenHammer (25-03-2024)

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Preface: It is possible to trigger Rowhammer bit flips on DDR4 devices on AMD Zen 2 and Zen 3 systems despite deployed TRR mitigations, said researchers at ETH Zurich.

Background: When high-energy charged particles pass through the crystal lattice of a silicon wafer, their charges can interfere with the electrons within the lattice itself and provide energy. If the lattice is moved closer together within the wafer, this disturbed electron trajectory can create a temporary highly conductive path that did not exist before. The effect of this trace is similar to running a very thin wire across the wafer in random directions. If the particle’s path crosses a feature within the die, such as a floating MOSFET gate or an NMOS DRAM cell, the result may be a flipped bit.

Vulnerability details: On February 26, 2024, AMD received new research related to an industry-wide DRAM issue documented in “ZENHAMMER: Rowhammering Attacks on AMD Zen-based Platforms” from researchers at ETH Zurich. The research demonstrates performing Rowhammer attacks on DDR4 and DDR5 memory using AMD “Zen” platforms. Given the history around Rowhammer, the researchers do not consider these rowhammering attacks to be a new issue.

Mitigation: Please see the following official announcement for details – https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7021.html

Science

International Space Station slipping across the Moon’s face as it flies by at 8 kilometers per second (8th Mar 2024)

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The moon and the earth rotate synchronously, so people on Earth can only see the same side of the moon throughout their lives. Because the moon also rotates, people on Earth cannot see the other side (see Figure L1a). There are also days when the moon faces away from the sun. It was pitch black at this time. Even if the International Space Station orbited the moon, it was pitch dark for part of the time because it faced away from the sun.

The gravitational force of two large masses is equal to the centripetal force required for small objects to move accordingly. Therefore, the moon falls at the Lagrangian point between the sun and the earth (L1, L1a & L3). NASA announce (James Webb) The Abel Space Telescope is also a Lagrangian point. (See attached picture L1, L2 & L3). I wonder if there is a chance to see the other side of the moon?


Ref: Please refer to the link for details – https://www.facebook.com/groups/355731256819830/permalink/421271603599128/

AI and ML, Science

LiDAR assists archaeologist discovered ruins found in upper Amazon rainforest (15th Jan 2024)

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Preface: In ancient time of South America Tribal leaders would cover their bodies with gold powder and wash themselves in a holy lake in the mountains. For example, the famous place for ancient civilization execute this ceremony is Lake Titicaca. Priests and nobles would throw precious gold and emeralds into the lake dedicated to God.

El Dorado, so called the Golden Kingdom is an ancient legend that first began with a South American ritual. Spanish Conquistadors, upon hearing these tales from the natives, believed there was a place abundant in gold and precious stones and began referring to it as El Dorado. Many explorers believe that Ciudad Blanca is the legendary El Dorado. Legend has it that somewhere beneath the forest canopy lies the ancient city of Ciudad Blanca and now archaeologists think they may have found it.

A group of scientists from fields including archaeology, anthropology and geology  using new technology known as airborne light detection and ranging (LiDAR). They found what appears to be a network of plazas and pyramids, hidden for hundreds of years in the underneath of the forest.

Background: What is LiDAR? LiDAR (light detection and ranging) is a remote sensing method that uses a laser to measure distances. Pulses of light are emitted from a laser scanner, and when the pulse hits a target, a portion of its photons are reflected back to the scanner. Because the location of the scanner, the directionality of the pulse, and the time between pulse emission and return are known, the 3D location (XYZ coordinates) from which the pulse reflected is calculable.

Which software is used for LiDAR data processing?

While LiDAR is a technology for making point clouds, not all point clouds are created using LiDAR. For example, point clouds can be made from images obtained from digital cameras, a technique known as photogrammetry. The one difference to remember that distinguishes photogrammetry from LiDAR is RGB. Unlike the RGB image, the LIDAR projection image does not have obvious texture, and it is difficult to find patterns in the projected image.

The programs to process LiDAR are numerous and increasing rapidly in accordance with the evolving field and user needs. ArcGIS has LiDAR processing functionality. ArcGIS accepts LAS or ASCII file types and has both 2D and 3D visualization options. Additionally, there are other options on the market. For example: NVIDIA DeepStream Software Development Kit (SDK). This SDK is an accelerated AI framework to build pipelines. DeepStream pipelines enable real-time analytics on video, image, and sensor data.

The architecture diagram on the right is for reference.

Headline News: https://www.sciencenews.org/article/ancient-urban-complex-ecuador-amazon-laser

Application Development, Science

Pulling back the curtain on Python satellite technology (24th Nov 2023)

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Preface: Satellite communications use the very high-frequency range of 1–50 gigahertz (GHz; 1 gigahertz = 1,000,000,000 hertz) to transmit and receive signals. The frequency ranges or bands are identified by letters: (in order from low to high frequency) L-, S-, C-, X-, Ku-, Ka-, and V-bands. The band 435- 438 MHz is heavily used for amateur satellites in accordance with No. 5.282. No. 5.278 (WRC-19) provides primary status for the amateur service at 430-440 MHz in 11 countries in Region 2.

Background: About twenty-five years ago, satellites were advanced technology. Satellite technology services, especially GPS, have become commonplace today. Perhaps it is an invisible force that makes development stronger and stronger. Who is this knight? It is the Python programming language technology. But you may ask, why do people always say that Python program development has a large share in the industrial world including aerospace technology. Long story short, Python has ready-made software modules, and software developers can use similar concepts to start their new development. This is the advantage of open source software.

Pulling back the curtain on Python satellite technology: gr-satellites is an OOT module encompassing a collection of telemetry decoders that supports nearly 40 different Amateur satellites. This open-source project started in 2015 with the goal of providing telemetry decoders for all the satellites that transmit on the Amateur radio bands.

gr-satellites is a GNU Radio out-of-tree module encompassing a collection of telemetry decoders that supports many different Amateur satellites.It supports most popular protocols, such as AX.25, the GOMspace NanoCom U482C and AX100 modems, an important part of the CCSDS stack, the AO-40 protocol used in the FUNcube satellites, and several ad-hoc protocols used in other satellites.

The KISS frame allow transmission of AX.25 packet radio frames containing IP packets over an asynchronous serial link.

KISS stands for “Keep It Simple, Stupid” and is not only a design principle, but also one of the most used Host-to-TNC communication protocols in HAM Radios. It is a very simple protocol that standardizes the transmission of data, normally AX.25 packets, over a asynchronous serial link, like RS232 or UART. It allows the transmission any arbitrary data, with no length limitation.

Reference: Using GPS in amateur radio is about GPS and other GNSS (Global Navigation Satellite System) satellites and how we can use the data broadcast by them for amateur radio. You will find that GPS benefits in digital modes like FT8, WSPR, and WSJT which rely on accurate transmit and receive period timing and this is easy to achieve with internet access to international time servers.

Please refer to the link for details:

https://orbitntnu.com

https://github.com/daniestevez/gr-satellites