A Tale of Two GPU’s

Story background: Rowhammer Attacks on GPU Memories are Practical (8th Dec 2025)

Preface: The story unfolds a hidden tale within two different design purpose GPUs (consumer display card and AI (install ROCm)) and reveals the untold behind-the-scenes story that the two sides concealed from the recent.

Background: AMD’s bulletin (Dec 2025) confirms GDDR6-based GPUs are vulnerable, but these are consumer display cards, not ROCm-enabled compute cards. This means AMD acknowledges Rowhammer risk on gaming GPUs, even if ROCm isn’t supported. Rowhammer risk exists for certain display (graphics) cards, specifically those with GDDR6 memory used in workstation and data center environments. Researchers recently demonstrated the “GPUHammer” attack, the first successful Rowhammer exploit on a discrete GPU, which can induce bit flips and compromise data integrity or AI model accuracy.

Rowhammer bit flips happen when repeatedly activating (hammering) specific DRAM rows causes electrical interference that causes adjacent “victim” rows to leak charge and flip their stored bit values. This vulnerability exploits the physical limitations of modern, high-density DRAM chips where cells are packed closely together, making them susceptible to disturbance errors.

Does Rowhammer Show on Screen?

Rowhammer is a memory integrity attack, not a rendering pipeline attack. Here’s why:

The workflow you described (PCIe → GDDR6 → cores → display controller) is correct for rendering.

Rowhammer flips bits in memory rows, potentially corrupting data structures (e.g., textures, buffers, or even code).

If the corrupted data is part of a framebuffer or texture, visual artifacts could appear on screen (e.g., glitches, wrong colors).

But if the corruption affects non-visual data (e.g., shader code, compute buffers), you might see crashes or silent errors instead.

So: it can manifest visually, but only if the hammered rows store display-related data.

AMD Official article: Please refer to the link for details.

https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7049.html

As a viewer, what will I think about when 3I/ATLAS approaches Regulus in Leo on December 19, 2025? (6th Dec 2025)

Preface: Comet 3I/ATLAS will be near Regulus (the “Heart of the Lion”) in the constellation Leo around its closest approach to Earth on December 19, 2025, appearing just below the bright star in the early pre-dawn, east-northeast sky, though a telescope is needed to see the faint comet itself.

About 3I/ATLAS: 3I/ATLAS offers scientists a rare opportunity to glimpse the constituent elements of another star system, but it also exhibits some unusual features, such as high carbon dioxide content, nickel-rich dust, and exotic gas escapes, all of which challenge conventional comet theories, although mainstream science tends to believe it is a comet.

Regarding the unexplained phenomena – the questions raised by Dr. Loeb: Dr. Avi Loeb deduced that the interstellar astronomy 3I/ATLAS may have lost a significant amount of mass, possibly tens of billions of tons, especially near the Sun. He drew this conclusion from the object’s rapid brightening before perihelion and the lack of detectable non-gravitational acceleration.

Ref: To know if an object has non-gravitational acceleration, you calculate its expected orbital path based only on gravity and compare it to its actual observed path; any significant deviation reveals a non-gravitational force, often from outgassing in comets (like a rocket), requiring complex modeling of mass loss, momentum transfer, and sublimation rates to quantify.

Examples in Action: A rocket expels mass (hot gas) backward, gaining momentum in the forward direction (Newton’s Third Law).

As a viewer, what will I think about when 3I/ATLAS approaches Regulus in Leo on December 19, 2025?

From a technological perspective, if a highly advanced civilization were to explore our solar system, they would be astonished to find that Earth possesses an atmosphere to protect it from comet impacts. Furthermore, Earth has a magnetic field to shield it from solar storms. Perhaps even a highly advanced civilization would find this structure extraordinary. We also have the Moon to regulate Earth’s tides. Perhaps the 3I/ATLAS probe knows that this solar system is under the control of another highly advanced civilization.

Professor Loeb’s recent article – Please refer to the link for details –

https://medium.com/@avi-loeb/image-of-3i-atlas-from-the-juice-navigation-camera-7ef8a5ef5e30

CVE-2025-47372: Buffer Copy Without Checking Size of Input in Boot (5th Dec-2025)

Qualcomm – Official announcement: 1st Dec 2025

Quote: I chose a Qualcomm product affected by this vulnerability as an example. The Snapdragon Ride™ Flex SoC, including the SA9000P series, does not run on a single embedded OS, but rather supports mixed-criticality operating systems such as those provided by Qualcomm’s partners or the automaker themselves.

Preface: Secure boot is defined as a boot sequence in which each software image to be executed is authenticated by software that was previously verified. This sequence is designed to prevent unauthorized or modified code from being run. Our chain of trust is built according to this definition, starting with the first piece of immutable software to be run out of read-only-memory (ROM). This first ROM bootloader cryptographically verifies the signature of the next bootloader in the chain, then that bootloader cryptographically verifies the signature of the next software image or images, and so on.

Background: Unlike other signed software images, the signature for Qualcomm Technologies signed images is only computed over a single segment in the image and not the entire image. The segment containing the signature is called the hash segment. This hash segment is a collection of the hash values of the other ELF segments that are included in the image. In other words we sign the collection of ELF segment hashes, rather than signing the entire ELF image. This representation is designed to relax memory size requirements and increases flexibility during loading.

Vulnerability details: The vulnerability described (CVE-2025-47372) is a heap overflow caused by reading an oversized ELF image into a buffer without proper bounds checking or authentication.

•       The overflow occurs during the write operation, before free() is called.

•       Once data exceeds the allocated size, adjacent memory is already corrupted.

•       Freeing memory only releases the block back to the allocator; it cannot undo corruption or prevent exploitation.

Official announcement: Please refer to the link for details

https://docs.qualcomm.com/product/publicresources/securitybulletin/december-2025-bulletin.html

CVE-2025-47319: Exposure of Sensitive System Information to an Unauthorized Control Sphere in HLOS (4th Dec 2025)

Published: 12/01/2025

Preface: Qualcomm HLOS (High-Level Operating System) refers to the operating system layer, like Android, that runs on a Qualcomm Snapdragon chipset and is responsible for general device functionality. “TA” (Trusted Application) is a component of the Qualcomm Trusted Execution Environment (QTEE) that runs in a secure environment, separate from the HLOS. Security issues arise when vulnerabilities exist at the boundary between the HLOS and a TA, such as memory corruption when the HLOS improperly processes commands from a TA, as described in Qualcomm security bulletins.

Background: The Qualcomm Secure Execution Environment Communication (QSEECom) lifecycle describes how a client application in the normal world interacts with a trusted application (TA) in the secure world via the qseecom kernel driver.

Step 1. QSEECom_start_app: Loads the TA into QTEE and allocates shared memory (ion_sbuffer) for communication.

Step 2. ion_sbuffer: The shared memory buffer used for both input and output.

Step 3:QSEECom_send_cmd: Sends a command to the TA, using the shared buffer.

Step 4: QSEECom_shutdown_app: Cleans up and unloads the TA.

Vulnerability details: CVE-2025-47319

  • Component: High-Level Operating System (HLOS)
  • Nature: Design weakness in buffer size calculation when processing commands from a Trusted Application (TA).
  • Impact: Could lead to buffer overflow, exposing sensitive system information and enabling arbitrary code execution.
  • Severity: Qualcomm rates it as critical, though its CVSS score is medium.
  • Discovery: Internal Qualcomm security team.

Mitigation: Patches have been shared with OEMs; users should update devices promptly.

Official announcement: Please refer to the link for details –

https://docs.qualcomm.com/product/publicresources/securitybulletin/december-2025-bulletin.html

CVE-2025-66216: About AIS-catcher (3rd Dec 2025)

Preface: AIS-Catcher is a MIT licensed dual band AIS receiver for Linux, Windows and Raspberry Pi. It is compatible with RTL-SDR dongles and the Airspy HF+.

AIS stands for Automatic Identification System and is used by marine vessels to broadcast their GPS locations in order to help avoid collisions and aide with rescues. An RTL-SDR with the right software can be used to receive and decode these signals, and plot ship positions on a map.

Background: You can set up your own receiver at home. With just a small USB radio adapter and a simple antenna, you can receive live signals from nearby ships and decode them directly on your computer or Raspberry Pi.

Setup requirement for an SDR AIS Receiver:

-RTL-SDR dongle (e.g. Nooelec NESDR, RTL-SDR Blog V3)

-VHF antenna (marine band, tuned for ~162 MHz)

-Raspberry Pi (Model 3 or later) or any PC

-Internet connection (for updates, optional data sharing)

Recommended Command (Dual-channel AIS, Auto Gain)

This does the following:

-A listens to both AIS frequencies:

Channel 1: 161.975 MHz

Channel 2: 162.025 MHz

-g auto lets AIS-catcher automatically choose the gain setting

Uses default device (-d 0) unless otherwise specified

You should see continuous outputs like this:

!AIVDM,1,1,,B,15MuqP001oK>rWnE`D0?;wvP0<2R,0*6D

These are raw NMEA AIS messages being received in real time.

Vulnerability details: CVE-2025-66216 – AIS-catcher is a multi-platform AIS receiver. Prior to version 0.64, a heap buffer overflow vulnerability has been identified in the AIS::Message class of AIS-catcher. This vulnerability allows an attacker to write approximately 1KB of arbitrary data into a 128-byte buffer. This issue has been patched in version 0.64.

Best Practices:

Never store data() pointer across operations that can reallocate (like push_back, resize, insert, emplace).

If you need a stable pointer, consider:

  • std::deque (doesn’t invalidate all pointers on growth).
  • std::vector::reserve() before operations to avoid reallocation.
  • Or use indices instead of raw pointers.

Official announcement: Please refer to the link for details – https://www.tenable.com/cve/CVE-2025-66216

CVE-2025-12183: About official lz4-java library (2nd Dec 2025)

Published: 2025-11-28

Preface: Apache Hadoop and Apache Spark are both prominent and widely used frameworks for big data analytics. They are central to the processing and analysis of large datasets that cannot be handled by traditional data processing tools.

Apache Hadoop utilizes the MapReduce programming model as a core component for processing and analyzing large datasets in a distributed manner.

How memory is used in Hadoop? Application MemoryHadoop applications, such as those running on YARN (Yet Another Resource Negotiator), also utilize RAM for their processing needs. For instance, MapReduce tasks and Spark applications perform computations in memory, leveraging RAM for faster data access and processing.

Background: LZ4 is a very fast lossless compression algorithm, providing compression speed > 500 MB/s per core, scalable with multi-cores CPU. It also features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed limits on multi-core systems.

The liblz4-java[.]so file is a native shared library that provides the underlying LZ4 compression and decompression functionality for the lz4-java library in Java applications.

From technical point of view,  liblz4-java[.]so acts as the high-performance engine for LZ4 operations, while the Java lz4-java library provides a convenient and type-safe API for Java developers to interact with this engine.

Remark: Since the maintainers of the official lz4-java library could not be contacted, the lz4 organization decided to discontinue the project.

Vulnerability details:

CVE-2025-12183 – Out-of-bounds memory operations in org.lz4:lz4-java 1.8.0 and earlier allow remote attackers to cause denial of service and read adjacent memory via untrusted compressed input.

Official announcement: Please refer to the link for details –

https://www.tenable.com/cve/CVE-2025-12183