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Automatic Key Exchange: faster, post-quantum secure origin handshakes for 45 billion daily connections (and counting)

Cloudflare's Automatic Key Exchange probes origins to lead with preferred key exchange, cutting HelloRetryRequests from 52% to 3.7% and enabling automatic post-quantum origin connections.

Cloudflare announced Automatic Key Exchange, an extension of Automatic SSL/TLS that probes each origin's supported key agreement algorithms and leads with the preferred one, favoring the post-quantum hybrid X25519MLKEM768. Rollover across roughly 45 billion daily origin connections cut HelloRetryRequests from about 52% to 3.7%, saving more than 150 ms of p90 handshake latency. Hundreds of thousands of domains now receive post-quantum origin connections without manual configuration, supporting Cloudflare's goal of quantum-safe encryption by 2029 to counter harvest-now-decrypt-later attacks.

Cloudflare Blog · 8d agoResearch

terms.txt: A Consent and Compensation Protocol for Agentic Web Access

terms.txt specifies a robots.txt-style protocol for per-path, per-purpose AI crawler consent and compensation, with enforcement adding 0.20-0.65 ms per request.

The paper documents that automated clients now make up most web requests, that training dominates Cloudflare-classified crawling, and that the largest AI platforms fetch thousands of pages per returned visitor while robots.txt cannot express identity, purpose, terms, or price. It specifies terms.txt plus an origin-enforced exchange using Web Bot Auth signatures, signed intent, delegation tokens, HTTP 402 negotiation, and signed receipts. A dependency-free implementation adds 0.20 to 0.65 ms per request on one vCPU.

arXiv cs.CR · 6d agoResearch

AD Rights Management Service (Part 1): Architecture, Deprecation, and Reconnaissance

Huntress maps AD RMS architecture and recon paths, setting up an offline key-extraction attack against its unrotatable 255-year root key.

Huntress's multi-part research examines Active Directory Rights Management Services, Microsoft's enterprise DRM role that still ships in Windows Server 2025 despite migration guidance favoring Azure Information Protection. Part 1 covers the trust model and how an ordinary domain account can locate RMS clusters and read rights-policy templates. Part 2 will detail four independent paths for extracting the Server Licensor Certificate (SLC) private key via service-group membership and the configuration database, enabling fully offline decryption of protected documents. The SLC certificate is valid from 2002 to 2258 and has no key-rotation mechanism, so a stolen key decrypts protected content indefinitely.

Huntress · 9d agoResearch1

SEEK: Secure and Efficient Encrypted Keyword Search For Privacy-Preserving Messaging Protocolsnew

Researchers propose SEEK, a homomorphic-encryption plus 2PC protocol for encrypted keyword search that hides keywords while detecting matches.

SEEK partitions messages into ciphertext fragments with minimum sufficient overlap and homomorphically correlates them using encrypted keyword trapdoors, combined with 2PC-based selected decoding, blinded zero testing, and secure aggregation. It reduces sender-side encryption and upload overhead by up to two orders of magnitude over state-of-the-art baselines and computes correlations up to 5.47x faster, revealing only the keyword presence bit while hiding contents, counts, and locations. A prototype achieves 1.92 seconds online computation per search on a weekly messaging history and is realized as a web and cross-platform mobile application.

arXiv cs.CR · 17h agoResearch

Detecting Logic Vulnerabilities Across the Contract and Device Layers of Blockchain-Enabled IoT With Multi-Agent Heterogeneous Graph Attentionnew

MA-HGAT framework detects logic vulnerabilities across smart contract and IoT device firmware layers using multi-agent heterogeneous graph attention.

Researchers extend MA-HGAT into a cross-layer multi-agent heterogeneous graph attention framework that models smart contracts, firmware artifacts, device fleets, and transaction streams for blockchain-enabled IoT security. A four-role, nine-relation schema supports graph-, link-, and node-level detection tasks, while a gateway-cloud partition enables lightweight edge inference on resource-constrained devices.

arXiv cs.CR · 19h agoResearch

Closing the Loop: Bidirectional Fully Encrypted Protocols

Researchers show naively composing unidirectional fully encrypted protocols is detectable and construct provably secure bidirectional FEPs, validated in Rust.

The paper introduces formal security definitions for bidirectional fully encrypted protocols (BiFEPs), covering exact shaping, delivery, protocol-state integrity, private half-close, and cross-direction isolation. It shows trivially composing two unidirectional FEPs enables detection attacks via cross-direction dependencies like traffic imbalance and connection tear-down. The authors construct provably secure BiFEPs for datastream and datagram settings, validated with a Rust implementation; no surveyed deployed protocol provides the full set of properties.

arXiv cs.CR · 1d agoResearch

Observational Indistinguishability and Integrity Blind Regions in Hybrid Quantum-Classical Workflows

Framework formalizes integrity blind regions in hybrid quantum-classical workflows, validated across 3,600 label interventions with conformal detection rules.

The paper presents a claim-relative evidence and reference framework for integrity of hybrid quantum-classical workflows, distinguishing structural blind regions caused by observational indistinguishability from finite-batch statistical misses. Experiments over 3,600 label interventions show exact label-path invariance for feature and prediction views. The geometry-aligned construction detects 343 of 2,700 conclusion-changing interventions using the conformal rule and 1,183 of 2,700 with the uncorrected union, with executed conformal clean false-action rates of 0.048-0.059.

arXiv cs.CR · 1d agoResearch

Hackers Turn Windows Shadow Copies Into a Tool for Credential Theft and Ransomware

Attackers abuse Windows VSS shadow copies to delete recovery points before ransomware and to extract NTDS.dit/SAM credentials, demanding context-aware detection.

Threat actors are weaponizing the Volume Shadow Copy Service (VSS) for two purposes: destroying local recovery points via vssadmin.exe, wmic.exe, diskshadow.exe, wbadmin.exe, and bcdedit.exe before encryption, and accessing static copies of locked files such as NTDS.dit and SAM for credential theft. Ransomware families tied to shadow-copy removal include Akira, Black Basta, BlackCat, Conti, LockBit, Qilin, RansomHub, REvil, Ryuk, and WannaCry. Huntress's analysis of the Nightmare-Eclipse tool showed the BlueHammer technique chaining a Windows Defender timing issue with a VSS snapshot to dump the SAM database and decrypt NT hashes. Defenders should correlate VSS operations with parent process, hive access, and subsequent encryption activity, and maintain immutable off-host backups.

GBHackers · 1d agoResearch in the wild1

gr-PHYSEC: Real-time Channel-based Key Generation for Physical Layer Secure Wireless Communications

gr-PHYSEC GNU Radio module derives symmetric encryption keys from wireless channel randomness using a neural network, validated on robotic platforms with ADALM-Pluto SDRs.

The paper introduces gr-PHYSEC, a GNU Radio out-of-tree module for real-time physical-layer key generation that derives symmetric keys from the wireless channel's inherent randomness instead of pre-shared secrets. A trained neural network extracts channel features between trusted parties during probe exchanges; features are quantized into binary keys, reconciled via Reed-Solomon encoding, and secured with SHA-512 hashing before direct use for encryption. Real-world experiments at the FAU CAAI connected robotics testbed using ADALM Pluto software-defined radios and NVIDIA Jetson Orin demonstrated low key disagreement rates and NIST-verified randomness. Source code is publicly available on GitHub.

arXiv cs.CR · 2d agoResearch

New DDRop Attack Breaks Intel TDX and AMD SEV-SNP Confidential Computing

DDRop uses a sub-$200 DDR5 interposer to drop memory writes, breaking Intel TDX and AMD SEV-SNP confidentiality guarantees.

Researchers at KU Leuven, ETH Zurich, Durham University, and Google will present DDRop at ACM CCS 2026, a first active interposer attack on DDR5 that silently drops memory writes so processors keep reading stale encrypted data, exploiting the missing freshness guarantee in Intel TDX, Intel Scalable SGX, and AMD SEV-SNP. On Intel TDX's default logical integrity mode it enabled reading victim VM memory, toggling debug mode, and forging remote attestation; AMD SEV-SNP was limited to copying pages between VMs. TDX's stronger cryptographic integrity blocks cross-VM attacks but likely not attestation forgery. The team will release board designs, firmware, and attack code on GitHub; no evidence of real-world use exists and no simple patch is available.

The Hacker Newsupdated · 1d agofirst · 2d agoResearch 2 sources

SpliTEE: Improving LLM Inference on Trusted Hardware with Differentially Private GPU Outsourcing

SpliTEE splits LLM inference between Intel TDX trusted execution and untrusted GPUs, using differential privacy instead of encryption to protect intermediate representations.

SpliTEE extends split inference to LLMs, running inference partly inside an Intel TDX TEE while masking intermediate inputs sent to untrusted GPUs with differential privacy rather than encryption. The authors show a prompt-reconstruction attack recovers nearly 80% of prompts from unmasked intermediate representations, motivating the masking. A global sensitivity analysis bounds the required DP noise scale, avoiding quantization and keeping models in floating point. The implementation is nearly twice as fast as full CPU-based TDX inference and 5-15 seconds faster than encryption-based Slalom with higher accuracy, evaluated on Llama-3.2-3B and Qwen3-4B.

arXiv cs.CR · 2d agoResearch

Accountability in Certificate Transparency and Variants

Formal Dolev-Yao analysis shows plain Certificate Transparency requires an honest log, SCT Auditing removes that assumption, and Gossiping does not.

The paper analyzes accountability in Certificate Transparency and its SCT Auditing and Gossiping extensions in the Dolev-Yao model, starting from a vanilla PKI. It finds plain CT provides accountability only under the assumption of an honest log. The SCT Auditing extension can eliminate that assumption, while the Gossiping extension cannot. CT is supported by all major browsers and obliges Certificate Authorities to record issued certificates in public, monitored logs.

arXiv cs.CR · 6d agoResearch

The Machine With Many Faces: Post-Exploitation Identity Misuse in SPIFFE/SPIRE

Unit 42 demonstrates that root access on a Kubernetes node lets attackers spoof SPIFFE/SPIRE attestation and harvest co-located workloads' SVIDs.

Palo Alto Networks Unit 42 describes post-exploitation techniques in which an attacker with root on a compromised Kubernetes node spoofs Linux cgroup metadata used by the SPIRE agent during workload attestation, tricking it into issuing a co-located workload's SPIFFE Verifiable Identity Document to an attacker-controlled process. The research shows the core trust assumption of machine-identity systems—that the node is trusted—collapses once root is obtained, exposing all cryptographic identities scoped to that node. Unit 42 released an open-source tool, Spooffe, for defenders to test identity exposure, and notes the technique has not been observed exploited in the wild.

Palo Alto Unit 42 · 6d agoResearch1

Session Attestation for Unmodified TLS Services in Confidential Virtual Machines

SessionLatch adds session attestation to unmodified TLS services in confidential VMs, cutting short-upload latency 63.1% versus TNG on Hygon CSV.

SessionLatch provides session attestation for confidential virtual machines without modifying applications, TLS implementations, or certificates. It relies on trusted observation of the server's locally generated ephemeral public key combined with standard TLS key confirmation, moving attestation integration to the operating system via a temporary latch that overlaps evidence exchange with the TLS handshake. Implemented with Linux and Windows integrations and evaluated on real Hygon CSV attestation, it reduces short-upload mean latency by 63.1%/23.0% relative to TNG in interleaved Linux/Windows experiments, while preserving enterprise service authentication and the native TLS data path, and supports mutual attestation.

arXiv cs.CR · 8d agoResearch

Has anybody seen my keys? A key-hierarchy strategy for rack-level security

Oxide's RFD 0301 proposes a rack-level key hierarchy using Shamir secret sharing and a trust quorum to protect data-at-rest keys.

Oxide's request for discussion (RFD 0301) lays out a key-hierarchy strategy for rack-level security, deriving keys from a rack secret protected by Shamir secret sharing across a trust quorum of sleds, with keys exchanged over authenticated sprockets sessions. The document maps which keys protect control-plane data, metrics, Crucible extents, and authentication tokens, and defines open questions on key lifecycle, locality, and compromise handling. Future work includes sealing shares with the root of trust so an attacker would need to steal K whole sleds to reconstruct the rack secret.

Your Shredded Visa Card May Still Work at the Checkout

UMass Amherst researchers demonstrated expired Visa contactless cards can complete real purchases via relay attacks exploiting Visa Kernel 3's unsigned expiry date handling.

University of Massachusetts Amherst researchers presented at USENIX Security 2026 that expired Visa contactless cards can be revived for real purchases through an NFC man-in-the-middle attack on Visa's Kernel 3. The attack alters the expiry date the terminal sees (tag 5F24) while leaving the Track 2 Equivalent Data (tag 57) sent to the issuing bank unchanged, and the card's cryptographic signature does not cover the expiry date. Two Android phones emulating card and terminal relayed transactions within Visa's 500-millisecond limit. Mastercard, American Express, and Discover kernels blocked the attack, while Visa Kernel 3 did not; researchers also modified the Consumer Device Cardholder Verification Method flag at five US banks, and attackers can also exploit Terminal Verification Results zero-filling. Visa was notified in May 2025 and December 2025; no CVE has been assigned.

Security Affairs · 26d agoResearch

Risky Bulletin: Academics find source code overlaps between Geedge and China's Great Firewall

Academics linked Chinese vendor Geedge Networks' Tiangou Secure Gateway source code to one of the Great Firewall's three traffic filtering capabilities.

US researchers presenting at USENIX Security reconstructed Geedge Networks' Tiangou Secure Gateway firmware from over 100,000 leaked files, including Git repositories with commit history, and matched its filtering behavior to sections of China's Great Firewall. They found only 1 of 3 characterized DNS injectors matched Geedge code, noted the system relies on memory-unsafe C components and copied third-party code, and said its bugs could aid future circumvention tools. Geedge also exports censorship tools to Kazakhstan, Ethiopia, Pakistan, and Myanmar. The newsletter additionally rounds up multiple breaches.

Risky Business News · 27d agoResearch2