OAuth2 is a delegation protocol that lets a user grant a third-party application limited access to their resources on a server, without sharing their credentials. Instead of handing over your username and password directly to the app, you authorize it through the resource server (like Google or Facebook). This authorization process generates an access token, which the app then uses to access specific resources on your behalf, within the scope you've permitted. OAuth2 focuses solely on authorization and not authentication, meaning it doesn't verify the user's identity. It relies on other mechanisms, like OpenID Connect, for that purpose.
DualQRCode.com offers a free online tool to create dual QR codes. These codes seamlessly embed a smaller QR code within a larger one, allowing for two distinct links to be accessed from a single image. The user provides two URLs, customizes the inner and outer QR code colors, and downloads the resulting combined code. This can be useful for scenarios like sharing a primary link with a secondary link for feedback, donations, or further information.
Hacker News users discussed the practicality and security implications of dual QR codes. Some questioned the real-world use cases, suggesting existing methods like shortened URLs or link-in-bio services are sufficient. Others raised security concerns, highlighting the potential for one QR code to be swapped with a malicious link while the other remains legitimate, thereby deceiving users. The technical implementation was also debated, with commenters discussing the potential for encoding information across both codes for redundancy or error correction, and the challenges of displaying two codes clearly on physical media. Several commenters suggested alternative approaches, such as using a single QR code that redirects to a page containing multiple links, or leveraging NFC technology. The overall sentiment leaned towards skepticism about the necessity and security of the dual QR code approach.
Little Snitch has a hidden "Deep Packet Inspection" feature accessible via a secret keyboard shortcut (Control-click on the connection alert, then press Command-I). This allows users to examine the actual data being sent or received by a connection, going beyond just seeing the IP addresses and ports. This functionality can be invaluable for troubleshooting network issues, identifying the specific data a suspicious application is transmitting, or even understanding the inner workings of network protocols. While potentially powerful, this feature is undocumented and requires some technical knowledge to interpret the raw data displayed.
HN users largely discuss their experiences with Little Snitch and similar firewall tools. Some highlight the "deny once" option as a valuable but less-known feature, appreciating its granularity compared to permanently blocking connections. Others mention alternative tools like LuLu and Vallum, drawing comparisons to Little Snitch's functionality and ease of use. A few users question the necessity of such tools in modern macOS, citing Apple's built-in security features. Several commenters express frustration with software increasingly phoning home, emphasizing the importance of tools like Little Snitch for maintaining privacy and control. The discussion also touches upon the effectiveness of Little Snitch against malware, with some suggesting its primary benefit is awareness rather than outright prevention.
A phishing attack leveraged Google's URL shortener, g.co, to mask malicious links. The attacker sent emails appearing to be from a legitimate source, containing a g.co shortened link. This short link redirected to a fake Google login page designed to steal user credentials. Because the initial link displayed g.co, it bypassed suspicion and instilled a false sense of security, making the phishing attempt more effective. The post highlights the danger of trusting shortened URLs, even those from seemingly reputable services, and emphasizes the importance of carefully inspecting links before clicking.
HN users discuss a sophisticated phishing attack using g.co shortened URLs. Several express concern about Google's seeming inaction on the issue, despite reports. Some suggest solutions like automatically blocking known malicious short URLs or requiring explicit user confirmation before redirecting. Others question the practicality of such solutions given the vast scale of Google's services. The vulnerability of URL shorteners in general is highlighted, with some suggesting they should be avoided entirely due to the inherent security risks. The discussion also touches upon the user's role in security, advocating for caution and skepticism when encountering shortened URLs. Some users mention being successfully targeted by this attack, and the frustration of banks accepting screenshots of g.co links as proof of payment. The conversation emphasizes the ongoing tension between user convenience and security, and the difficulty of completely mitigating phishing risks.
This post showcases a "lenticular" QR code that displays different content depending on the viewing angle. By precisely arranging two distinct QR code patterns within a single image, the creator effectively tricked standard QR code readers. When viewed head-on, the QR code directs users to the intended, legitimate destination. However, when viewed from a slightly different angle, the second, hidden QR code becomes readable, redirecting the user to an "adversarial" or unintended destination. This demonstrates a potential security vulnerability where malicious QR codes could mislead users into visiting harmful websites while appearing to link to safe ones.
Hacker News commenters discuss various aspects of the QR code attack described, focusing on its practicality and implications. Several highlight the difficulty of aligning a camera perfectly to trigger the attack, suggesting it's less a realistic threat and more a clever proof of concept. The potential for similar attacks using other mediums, such as NFC tags, is also explored. Some users debate the definition of "adversarial attack" in this context, arguing it doesn't fit the typical machine learning definition. Others delve into the feasibility of detection, proposing methods like analyzing slight color variations or inconsistencies in the printing to identify manipulated QR codes. Finally, there's a discussion about the trust implications and whether users should scan QR codes displayed on potentially compromised surfaces like public screens.
A vulnerability (CVE-2024-54507) was discovered in the XNU kernel, affecting macOS and iOS, which allows malicious actors to leak kernel memory. The flaw resides in the sysctl interface, specifically the kern.hv_vmm_vcpu_state handler. This handler failed to properly validate the size of the buffer provided by the user, resulting in an out-of-bounds read. By crafting a request with a larger buffer than expected, an attacker could read data beyond the intended memory region, potentially exposing sensitive kernel information. This vulnerability was patched by Apple in October 2024 and is relatively simple to exploit.
Hacker News commenters discuss the CVE-2024-54507 vulnerability, focusing on the unusual nature of the vulnerable sysctl and the potential implications. Several express surprise at the existence of a sysctl that directly modifies kernel memory, questioning why such a mechanism exists and speculating about its intended purpose. Some highlight the severity of the vulnerability, emphasizing the ease of exploitation and the potential for privilege escalation. Others note the fortunate aspect of the bug manifesting as a kernel panic rather than silent memory corruption, making detection easier. The limited practical impact due to System Integrity Protection (SIP) is also mentioned, alongside the difficulty of exploiting the vulnerability remotely. A few commenters also delve into the technical details of the exploit, discussing the specific memory manipulation involved and the resulting kernel crash. The overall sentiment reflects concern about the unusual nature of the vulnerability and its potential implications, even with the mitigating factors.
A misconfigured DNS record for Mastercard went unnoticed for an estimated two to five years, routing traffic intended for a Mastercard authentication service to a server controlled by a third-party vendor. This misdirected traffic included sensitive authentication data, potentially impacting cardholders globally. While Mastercard claims no evidence of malicious activity or misuse of the data, the incident highlights the risk of silent failures in critical infrastructure and the importance of robust monitoring and validation. The misconfiguration involved an incorrect CNAME record, effectively masking the error and making it difficult to detect through standard monitoring practices. This situation persisted until a concerned individual noticed the discrepancy and alerted Mastercard.
HN commenters discuss the surprising longevity of Mastercard's DNS misconfiguration, with several expressing disbelief that such a basic error could persist undetected for so long, particularly within a major financial institution. Some speculate about the potential causes, including insufficient monitoring, complex internal DNS setups, and the possibility that the affected subdomain wasn't actively used or monitored. Others highlight the importance of robust monitoring and testing, suggesting that Mastercard's internal processes likely had gaps. The possibility of the subdomain being used for internal purposes and therefore less scrutinized is also raised. Some commenters criticize the article's author for lacking technical depth, while others defend the reporting, focusing on the broader issue of oversight within a critical financial infrastructure.
Sigstore aims to solve the problem of software supply chain security by making it easy to sign software artifacts and verify those signatures. It provides free tooling and a public good transparency log, enabling developers to sign releases with short-lived certificates tied to their identities (e.g., GitHub and email). This allows users to easily verify the provenance and integrity of software, ensuring that it hasn't been tampered with and genuinely originates from the claimed source. Sigstore simplifies the complex process of code signing, removing the need for managing long-lived keys and complicated infrastructure. This makes it significantly more practical for developers to secure their software supply chains and builds trust with end users.
Hacker News commenters generally expressed strong support for Sigstore and its mission of improving software supply chain security. Several praised its ease of use and integration with existing tools, noting the significantly lowered barrier to entry for signing releases compared to traditional methods. Some highlighted the importance of key transparency and the clever use of OpenID Connect for identity verification. A few commenters discussed the potential impact on various ecosystems like Debian and Python, expressing hope for wider adoption and speculating on the future development of the project. Concerns were raised about the reliance on centralized services and potential single points of failure, but these were often met with counter-arguments about the federated nature of OpenID and the transparency of the log. Some users questioned the long-term viability of free certificate issuance, and others debated the nuances of different signing models and their relative security implications.
A security vulnerability, dubbed "0-click," allowed remote attackers to deanonymize users of various communication platforms, including Signal, Discord, and others, by simply sending them a message. Exploiting flaws in how these applications handled media files, specifically embedded video previews, the attacker could execute arbitrary code on the target's device without any interaction from the user. This code could then access sensitive information like the user's IP address, potentially revealing their identity. While the vulnerability affected the Electron framework underlying these apps, rather than the platforms themselves, the impact was significant as it bypassed typical security measures and allowed complete deanonymization with no user interaction. This vulnerability has since been patched.
Hacker News commenters discuss the practicality and impact of the described 0-click deanonymization attack. Several express skepticism about its real-world applicability, noting the attacker needs to be on the same local network, which significantly limits its usefulness compared to other attack vectors. Some highlight the importance of the disclosure despite these limitations, as it raises awareness of potential vulnerabilities. The discussion also touches on the technical details of the exploit, with some questioning the "0-click" designation given the requirement for the target to join a group call. Others point out the responsibility of Electron, the framework used by the affected apps, for not sandboxing UDP sockets effectively, and debate the trade-offs between security and performance. A few commenters discuss potential mitigations and the broader implications for user privacy in online communication platforms.
The post details the reverse engineering process of Call of Duty's anti-cheat driver, specifically version 1.4.2025. The author uses a kernel debugger and various tools to analyze the driver's initialization, communication with the game, and anti-debugging techniques. They uncover how the driver hides itself from process lists, intercepts system calls related to process and thread creation, and likely monitors game memory for cheats. The analysis includes details on specific function calls, data structures, and control flow within the driver, illustrating how it integrates deeply with the operating system kernel to achieve its anti-cheat goals. The author's primary motivation was educational, focusing on the technical aspects of the reverse engineering process itself.
Hacker News users discuss the reverse engineering of Call of Duty's anti-cheat system, Tactical Advantage Client (TAC). Several express admiration for the technical skill involved in the analysis, particularly the unpacking and decryption process. Some question the legality and ethics of reverse engineering anti-cheat software, while others argue it's crucial for understanding its potential privacy implications. There's skepticism about the efficacy of kernel-level anti-cheat and its potential security vulnerabilities. A few users speculate about potential legal ramifications for the researcher and debate the responsibility of anti-cheat developers to be transparent about their software's behavior. Finally, some commenters share anecdotal experiences with TAC and its impact on game performance.
This project describes a method to use an Apple device (iPhone or Apple Watch) as an access card even with unsupported access control systems. It leverages the device's NFC capabilities to read the card's data, then emulates the card using an Arduino and RFID reader/writer. The user taps their physical access card on the RFID reader connected to the Arduino, which then transmits the card data to an Apple device via Bluetooth. The Apple device then stores and transmits this data wirelessly to the Arduino when presented to the reader, effectively cloning the original card's functionality. This allows users to unlock doors and other access points without needing their physical card.
HN users discuss the practicality and security implications of using an Apple device as an access card in unsupported systems. Several commenters point out the inherent security risks, particularly if the system relies solely on NFC broadcasting without further authentication. Others highlight the potential for lock-in and the difficulties in managing lost or stolen devices. Some express skepticism about the reliability of NFC in real-world scenarios, while others suggest alternative solutions like using a Raspberry Pi for more flexible and secure access control. The overall sentiment leans towards caution, with many emphasizing the importance of robust security measures in access control systems.
A seemingly innocuous USB-C to Ethernet adapter, purchased from Amazon, was found to contain a sophisticated implant capable of malicious activity. This implant included a complete system with a processor, memory, and network connectivity, hidden within the adapter's casing. Upon plugging it in, the adapter established communication with a command-and-control server, potentially enabling remote access, data exfiltration, and other unauthorized actions on the connected computer. The author meticulously documented the hardware and software components of the implant, revealing its advanced capabilities and stealthy design, highlighting the potential security risks of seemingly ordinary devices.
Hacker News users discuss the practicality and implications of the "evil" RJ45 dongle detailed in the article. Some question the dongle's true malicious intent, suggesting it might be a poorly designed device for legitimate (though obscure) networking purposes like hotel internet access. Others express fascination with the hardware hacking and reverse-engineering process. Several commenters discuss the potential security risks of such devices, particularly in corporate environments, and the difficulty of detecting them. There's also debate on the ethics of creating and distributing such hardware, with some arguing that even proof-of-concept devices can be misused. A few users share similar experiences encountering unexpected or unexplained network behavior, highlighting the potential for hidden hardware compromises.
Rhai is a fast and lightweight scripting language specifically designed for embedding within Rust applications. It boasts a simple, easy-to-learn syntax inspired by JavaScript and Rust, making it accessible for both developers and end-users. Rhai prioritizes performance and safety, leveraging Rust's ownership and borrowing system to prevent data races and other memory-related issues. It offers seamless integration with Rust, allowing direct access to Rust functions and data structures, and supports dynamic typing, custom functions, modules, and even asynchronous operations. Its versatility makes it suitable for a wide range of use cases, from game scripting and configuration to data processing and rapid prototyping.
HN commenters generally praised Rhai for its speed, ease of embedding, and Rust integration. Several users compared it favorably to Lua, citing better performance and a more "Rusty" feel. Some appreciated its dynamic typing and scripting-oriented nature, while others suggested potential improvements like static typing or a WASM target. The discussion touched on use cases like game scripting, configuration, and embedded systems, highlighting Rhai's versatility. A few users expressed interest in contributing to the project. Concerns raised included the potential performance impact of dynamic typing and the relatively small community size compared to more established scripting languages.
The blog post "Let's talk about AI and end-to-end encryption" explores the perceived conflict between the benefits of end-to-end encryption (E2EE) and the potential of AI. While some argue that E2EE hinders AI's ability to analyze data for valuable insights or detect harmful content, the author contends this is a false dichotomy. They highlight that AI can still operate on encrypted data using techniques like homomorphic encryption, federated learning, and secure multi-party computation, albeit with performance trade-offs. The core argument is that preserving E2EE is crucial for privacy and security, and perceived limitations in AI functionality shouldn't compromise this fundamental protection. Instead of weakening encryption, the focus should be on developing privacy-preserving AI techniques that work with E2EE, ensuring both security and the responsible advancement of AI.
Hacker News users discussed the feasibility and implications of client-side scanning for CSAM in end-to-end encrypted systems. Some commenters expressed skepticism about the technical challenges and potential for false positives, highlighting the difficulty of distinguishing between illegal content and legitimate material like educational resources or artwork. Others debated the privacy implications and potential for abuse by governments or malicious actors. The "slippery slope" argument was raised, with concerns that seemingly narrow use cases for client-side scanning could expand to encompass other types of content. The discussion also touched on the limitations of hashing as a detection method and the possibility of adversarial attacks designed to circumvent these systems. Several commenters expressed strong opposition to client-side scanning, arguing that it fundamentally undermines the purpose of end-to-end encryption.
Multiple vulnerabilities were discovered in rsync, a widely used file synchronization tool. These vulnerabilities affect both the client and server components and could allow remote attackers to execute arbitrary code or cause a denial of service. Exploitation generally requires a malicious rsync server, though a malicious client could exploit a vulnerable server with pre-existing trust, such as a backup server. Users are strongly encouraged to update to rsync version 3.2.8 or later to address these vulnerabilities.
Hacker News users discussed the disclosed rsync vulnerabilities, primarily focusing on the practical impact. Several commenters downplayed the severity, noting the limited exploitability due to the requirement of a compromised rsync server or a malicious client connecting to a user's server. Some highlighted the importance of SSH as a secure transport layer, mitigating the risk for most users. The conversation also touched upon the complexities of patching embedded systems and the potential for increased scrutiny of rsync's codebase following these disclosures. A few users expressed concern over the lack of memory safety in C, suggesting it as a contributing factor to such vulnerabilities.
The blog post "Right to root access" argues that users should have complete control over the devices they own, including root access. It contends that manufacturers artificially restrict user access for anti-competitive reasons, forcing users into walled gardens and limiting their ability to repair, modify, and truly own their devices. This restriction extends beyond just software to encompass firmware and hardware, hindering innovation and consumer freedom. The author believes this control should be a fundamental digital right, akin to property rights in the physical world, empowering users to fully utilize and customize their technology.
HN users largely agree with the premise that users should have root access to devices they own. Several express frustration with "walled gardens" and the increasing trend of manufacturers restricting user control. Some highlight the security and repairability benefits of root access, citing examples like jailbreaking iPhones to enable security features unavailable in the official iOS. A few more skeptical comments raise concerns about users bricking their devices and the potential for increased malware susceptibility if users lack technical expertise. Others note the conflict between right-to-repair legislation and software licensing agreements. A recurring theme is the desire for modular devices that allow component replacement and OS customization without voiding warranties.
iOS 18 introduces a new feature that automatically reboots devices after a prolonged period of inactivity. Reverse engineering revealed this is managed by the SpringBoard process, which monitors user interaction and triggers a reboot after approximately 72 hours of inactivity. The reboot is signaled by setting a specific flag in a system property and is considered a "soft" reboot, likely to maintain device state where possible. This feature seems primarily targeted at corporate devices enrolled in Mobile Device Management (MDM) systems, as a way to clear temporary states and potentially address performance issues resulting from prolonged uptime without requiring manual intervention. The exact conditions for triggering the reboot, beyond inactivity time, are still being investigated.
Hacker News users discussed the potential reasons behind iOS 18's automatic reboot after extended inactivity, with some speculating it's related to memory management, specifically clearing caches or resetting background processes. Others suggested it could be a security measure to mitigate potential exploits or simply a bug. A few commenters expressed concern about the reboot happening without warning, potentially interrupting ongoing tasks or data syncing. Some highlighted the lack of official documentation on this behavior and the author's reverse engineering efforts to uncover the cause. The discussion also touched on similar behavior observed in other operating systems and the overall complexity of modern OS architectures.
Garak is an open-source tool developed by NVIDIA for identifying vulnerabilities in large language models (LLMs). It probes LLMs with a diverse range of prompts designed to elicit problematic behaviors, such as generating harmful content, leaking private information, or being easily jailbroken. These prompts cover various attack categories like prompt injection, data poisoning, and bias detection. Garak aims to help developers understand and mitigate these risks, ultimately making LLMs safer and more robust. It provides a framework for automated testing and evaluation, allowing researchers and developers to proactively assess LLM security and identify potential weaknesses before deployment.
Hacker News commenters discuss Garak's potential usefulness while acknowledging its limitations. Some express skepticism about the effectiveness of LLMs scanning other LLMs for vulnerabilities, citing the inherent difficulty in defining and detecting such issues. Others see value in Garak as a tool for identifying potential problems, especially in specific domains like prompt injection. The limited scope of the current version is noted, with users hoping for future expansion to cover more vulnerabilities and models. Several commenters highlight the rapid pace of development in this space, suggesting Garak represents an early but important step towards more robust LLM security. The "arms race" analogy between developing secure LLMs and finding vulnerabilities is also mentioned.
This paper introduces a new fuzzing technique called Dataflow Fusion (DFusion) specifically designed for complex interpreters like PHP. DFusion addresses the challenge of efficiently exploring deep execution paths within interpreters by strategically combining coverage-guided fuzzing with taint analysis. It identifies critical dataflow paths and generates inputs that maximize the exploration of these paths, leading to the discovery of more bugs. The researchers evaluated DFusion against existing PHP fuzzers and demonstrated its effectiveness in uncovering previously unknown vulnerabilities, including crashes and memory safety issues, within the PHP interpreter. Their results highlight the potential of DFusion for improving the security and reliability of interpreted languages.
Hacker News users discussed the potential impact and novelty of the PHP fuzzer described in the linked paper. Several commenters expressed skepticism about the significance of the discovered vulnerabilities, pointing out that many seemed related to edge cases or functionalities rarely used in real-world PHP applications. Others questioned the fuzzer's ability to uncover truly impactful bugs compared to existing methods. Some discussion revolved around the technical details of the fuzzing technique, "dataflow fusion," with users inquiring about its specific advantages and limitations. There was also debate about the general state of PHP security and whether this research represents a meaningful advancement in securing the language.
Summary of Comments ( 16 )
https://news.ycombinator.com/item?id=42829149
HN commenters generally praised the article for its clear explanation of OAuth2, calling it accessible and well-written, particularly appreciating the focus on the "why" rather than just the "how." Some users pointed out potential minor inaccuracies or areas for further clarification, such as the distinction between authorization code grant with PKCE and implicit flow for client-side apps, the role of refresh tokens, and the implications of using a third-party identity provider. One commenter highlighted the difficulty of finding good OAuth2 resources and expressed gratitude for the article's contribution. Others suggested additional topics for the author to cover, such as the challenges of cross-domain authentication. Several commenters also shared personal anecdotes about their experiences implementing or troubleshooting OAuth2.
The Hacker News post "What's OAuth2, anyway?" with the ID 42829149 generated a moderate amount of discussion with several insightful comments.
Many commenters praised the article for its clarity and simplicity in explaining a complex topic. One user appreciated the straightforward explanation, saying it was the first time they truly understood OAuth2. Another highlighted the article's effectiveness in breaking down the jargon and making the concepts accessible. Several others echoed this sentiment, expressing gratitude for the clear and concise explanation.
A significant part of the discussion revolved around the practical complexities and security considerations of OAuth2. One commenter pointed out the challenges of implementing OAuth2 securely, noting the potential for vulnerabilities if not handled carefully. They specifically mentioned the complexity introduced by refresh tokens and the potential for token leakage. Another user discussed the different OAuth2 grant types and their suitability for various use cases, highlighting the importance of choosing the appropriate grant type for the specific application.
Some commenters delved into the historical context of OAuth2, discussing its evolution and comparing it to previous authentication methods. One user explained how OAuth2 addressed some of the shortcomings of earlier approaches, while acknowledging its own complexities. Another discussed the challenges of migrating from older systems to OAuth2.
Several commenters shared their personal experiences and anecdotes related to OAuth2. One recounted a story about a challenging OAuth2 integration, emphasizing the practical difficulties encountered in real-world implementations. Another shared a helpful tip for debugging OAuth2 issues.
A few comments focused on specific aspects of the article, offering corrections or alternative perspectives. One commenter suggested a minor clarification regarding the terminology used, while another offered a different interpretation of a particular concept.
Overall, the comments on the Hacker News post provide a valuable supplement to the article itself, offering practical insights, diverse perspectives, and real-world experiences related to OAuth2 and its complexities. They highlight both the benefits of OAuth2 as a powerful authorization framework and the challenges involved in its proper implementation and use.