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Autoencoder Is All You Need: Profiling and Detecting Malicious DNS Traffic

Palo Alto Unit 42 details an autoencoder-based method that profiles DNS traffic to detect C2 and malicious domains, blocking ~374,000 malicious DNS requests daily.

Unit 42 built an RNN-based autoencoder that compresses DNS traffic time series into fixed-dimensional 'DNS profiles' for each domain and device. Downstream classification, clustering, and anomaly detection modules flag suspicious domains, capturing 170 emerging suspicious domains in May 2024. Signatures block roughly 374,000 malicious DNS requests daily and run in the Advanced DNS Security service, with detections shared to Advanced URL Filtering. Case studies link DNS traffic patterns to C2 beaconing, dynamic DNS abuse, and DNS tunneling for data exfiltration.

Palo Alto Unit 42 · Aug 17, 2026Research

Automatically Detecting DNS Hijacking in Passive DNS

Unit 42's machine learning pipeline detected 6,729 DNS hijacking events between March and September 2024, hitting political parties, ISPs, and universities.

Unit 42 processes roughly 167 million new DNS records daily and applies a machine learning model using 74 features over 169 TB of passive DNS and geolocation data to flag hijacked domains. From March to September 2024 the pipeline screened over 29 billion records and classified 6,729 as DNS hijacking, averaging 38 detections per day; a new model detects hijacks in customer traffic within about 10 minutes. Notable cases include a Hungarian political party's hijacked domain, defacement of a large utility company and ISP, and university and research center domains repurposed for illicit gambling. DNS hijacking typically relies on stolen registrar or DNS provider credentials or cache poisoning, enabling MitM attacks, phishing, drive-by downloads, and scams.

Palo Alto Unit 42 · Aug 17, 2026Research in the wild

Almost Half of Malware Samples Communicate Direct to IP

Unit 42 analysis of 4 million malware reports finds 45% of C2-active samples connect directly to hard-coded IPs, bypassing DNS defenses.

Palo Alto Unit 42 analyzed over 4 million Advanced WildFire dynamic analysis reports and found that 45.32% of malware samples with C2 activity made at least one direct-to-IP connection, accounting for 23.17% of all C2 connection attempts. The firm proposes zero trust IP (ZT-IP), an enforcement approach that verifies whether outbound destinations were ever sanctioned by a DNS response. ZT-IP analysis surfaced Phorpiex ransomware droppers fetching payloads directly from C2 IPs, a persistent data exfiltration campaign using an obfuscated \GET protocol, and Mozi P2P botnet payloads delivered to IoT devices without DNS. Only 1% of benign samples connected directly to untrusted IP addresses.

Palo Alto Unit 42 · Aug 17, 2026Research

Hacking Public Wi-Fi DNS to Steal Credentials

Attackers can hijack public Wi-Fi DNS to redirect users to credential-stealing fake login pages; commenters debate HTTPS limits and mitigations like encrypted DNS.

The discussion examines how an attacker controlling DNS on shared or public Wi-Fi networks can redirect requests for legitimate services to attacker-controlled servers to steal credentials. Commenters analyze whether HTTPS and certificates mitigate the attack, noting attackers often rely on HTTP or browser trust quirks. Suggested defenses include encrypted DNS (DoH), DNSSEC, and travel routers running OpenWRT. No specific campaign, victims, or indicators are provided.

Schneier on Security · Aug 17, 2026Research1

Recent Trends in Internet Threats: Common Industries Impersonated in Phishing Attacks, Web Skimmer Analysis and More

Unit 42 analyzed 67 million malicious URLs and domains in H2 2022, a 52% increase, highlighting phishing impersonation and web skimmer trends.

Unit 42 observed more than 67 million unique malicious URLs, domains and IPs between July and December 2022, a 52% increase over the first half of the year. Malicious JavaScript detections grew 99.3%, with over 4 million malicious JS samples hosted on 4.8 million URLs. Over 85% of hosting infrastructure was concentrated in eight countries, led by the United States, Brazil and China. The report also analyzes industries spoofed in phishing pages and includes a web skimmer case study on a Tranco top 1 million website.

Palo Alto Unit 42 · Aug 17, 2026Research

Cloudflare DDoS Threat Report H1 2026: 1 Tbps attacks soar as DNS floods and geopolitical tensions drive a new wave

Cloudflare's H1 2026 report records a 519% surge in hyper-volumetric DDoS attacks, driven by DNS and CLDAP reflection amid geopolitical tensions.

Cloudflare detected a 519% surge in hyper-volumetric DDoS attacks across its network during the first half of 2026. Attack traffic was driven heavily by DNS and CLDAP reflection vectors, with 1 Tbps attacks becoming far more common. The report attributes reshaped attack patterns to major geopolitical conflicts.

Cloudflare Blog · Aug 11, 2026Research

MacOS 27 - First Boot, (Tue, Sep 15th)

SANS ISC documents the expected network traffic macOS 27 'Golden Gate' generates on first boot to help defenders baseline their networks.

Johannes Ullrich of SANS Internet Storm Center captured roughly 300 packets from a macOS 27 'Golden Gate' system before user login, covering DHCP, IPv6 duplicate address discovery, DNS, and TCP behavior. macOS 27 resolves hostnames like albert.apple.com (device activation, certificate-pinned), push messaging hosts, and ipv4only.arpa for NAT64 networks. The OS still uses a TCP window scale of 6, ECN, and random timestamps, with only four TCP connections observed during boot. The analysis provides a reference baseline for security teams monitoring Apple endpoints.

SANS Internet Storm Center · 1d agoResearch

TLD Tracker: Exploring Newly Released Top

Unit 42 tracked 19 newly released top-level domains and found large-scale phishing, unwanted program distribution, and cybersquatting tied to TLD launch dates.

Researchers analyzed 19 new generic TLDs, including .zip, .bot, .ing, and .meme, released or approaching general availability over roughly 18 months. Data from passive DNS, registry zone files, newly registered domain feeds, and the Tranco top-1M list showed phishing campaigns, potentially unwanted program distribution, and domain squatting on these TLDs. Abuse correlated with each TLD's rollout phases, indicating attackers monitor general availability dates to register and weaponize domains. The IANA root database now lists over 1,000 generic TLDs.

Palo Alto Unit 42 · Aug 17, 2026Research

Beneath the Surface: Detecting and Blocking Hidden Malicious Traffic Distribution Systems

Unit 42 built an ML-based detector for malicious traffic distribution systems, finding malicious TDS chains average longer redirections and more URLs than legitimate ones.

Traffic distribution systems redirect victims through chains of intermediate domains to hide final destinations, serving phishing, malvertising, and online gambling operations. Unit 42's topological analysis of redirection graphs found malicious TDS traffic uses longer chains (about 25% exceed four hops vs 10% benign), more URLs (median 126 vs 80), and fewer isolated subgraphs with higher connectivity. These features power an ML detector integrated into Advanced DNS Security and Advanced URL Filtering to identify and block malicious TDS infrastructure in customer traffic.

Palo Alto Unit 42 · Aug 17, 2026Research

Trends in Web Threats in CY Q2 2022: Malicious JavaScript Downloaders Are Evolving

Unit 42 detected 751,000 landing URL incidents in Q2 2022 and documented malicious JavaScript downloaders evolving to evade detection.

Unit 42 detected 751,331 landing URL incidents (253,644 unique) and 1,744,629 malicious host URL incidents (256,844 unique) from April through June 2022. Total landing URL incidents rose compared with Q1 2022, and unique host URL incidents grew 42%, indicating attackers deploying more variants. The report includes a case study of a JavaScript downloader campaign demonstrating new evasion techniques. Personal sites, blogs, and business sites were the top apparently benign entry points.

Palo Alto Unit 42 · Aug 17, 2026Research

Introducing Unit 42’s Attribution Framework

Unit 42 releases its Attribution Framework, a systematic method using Diamond Model and Admiralty scores to attribute activity clusters to named threat actors.

Palo Alto Networks' Unit 42 introduced a structured framework for threat actor attribution built on the Diamond Model of Intrusion Analysis and Admiralty reliability/credibility scoring. The framework tracks activity at three levels: activity clusters (named CL-STA, CL-CRI, CL-UNK, or CL-MIX), temporary threat groups, and named threat actors using the constellation naming schema. Analysts score evidence across TTPs, tooling, malware code, OPSEC, infrastructure, timelines, and victimology to decide when to merge or elevate clusters, avoiding premature group naming.

Palo Alto Unit 42 · Aug 17, 2026Research

How Attackers Abuse VSS, and How Huntress Detects It

Huntress details how attackers abuse Windows Volume Shadow Copies for ransomware recovery sabotage and NTDS.dit credential theft, plus detection logic.

Huntress explains that attackers abuse VSS in three ways: deleting shadow copies to inhibit recovery before ransomware detonation, creating shadow copies to extract the NTDS.dit Active Directory database for offline credential theft, and manipulating shadow copy configuration. Because backup agents and RMM tools routinely create and delete shadow copies, raw events are too noisy to alert on alone. Huntress detections instead correlate VSS activity with lateral movement and credential harvesting over a time window, such as an observed sequence of PsExec spawning SYSTEM shells on a domain controller, vssadmin create shadow, a blocked deletion attempt, and DNS reconnaissance against another host.

Huntress · 2d agoResearch

Scareware ads keep running on Google's transparency tool, even after they're reported

NYU and Radboud researchers built AdLens, which found 238 scareware and 3,346 false-claim ads in Google's ad archive; reported ads often stayed live.

The AdLens tool, built by NYU and Radboud University researchers, mined Google's Ads Transparency Center and screened 188,000 software ad creatives using similarity search plus a panel of open-source language models, finding 238 scareware ads, 3,346 false-claim ads, and 258 anonymity-avoiding ads with over 100 million impressions in Europe. Reporting ads through Google's standard flow produced inconsistent removals: some ads acknowledged as violations stayed live, and after one takedown tied to the TamperedChef malware domain, 41 other ads pointing to the same domain kept running. The pipeline runs entirely on open-weight models at low cost (a $96 DigitalOcean VM plus $1.57/hour L40S inference) and is designed to extend to Meta and Amazon ad libraries.

Help Net Security · 15d 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

CDN Tsunami Attack Abuses HTTP/3 Translation for Up to 350x DoS Amplification

Researchers disclosed two DoS attacks exploiting CDNs' HTTP/3-to-HTTP/1.1 translation to amplify low-bandwidth requests up to 350x against origin servers.

Researchers named the two techniques HTTP/3 Bandwidth Amplification (HBA) and HTTP/3 Connection Amplification (HCA), exploiting the gap where CDNs speak HTTP/3 to browsers but only HTTP/1.1 to origins. All six tested CDNs (Alibaba, Baidu, Cloudflare, CloudFront, Fastly, Tencent) were susceptible to HBA, and five to HCA, with Cloudflare immune to HCA because it buffers full requests before opening backend connections. Attackers using under 5 Mbps forced over 100 Mbps at origins, and the 350x factor applies only to Alibaba, Baidu, and Tencent, which support the QPACK dynamic table. Testing identified 42,330 potentially vulnerable subdomains out of 151,685 hosted on the six providers across the Tranco Top 1M.

The Hacker News · 27d agoResearch

8,539 Reasons To Rethink How Vulnerabilities Get Patched

Rapid7 counted 8,539 high and critical CVEs in Q2 2026, double last year, with PoC availability up 76%.

Rapid7's Q2 2026 Threat Landscape Report tallied 8,539 high- and critical-severity vulnerability disclosures, twice the number recorded in Q2 2025, with newly disclosed flaws having public proof-of-concept code up 76% year over year. Of newly exploited vulnerabilities, 62% were network-exploitable and required neither authentication nor user interaction. Fake CAPTCHA and ClickFix social engineering accounted for 31.8% of incident response cases, the United States recorded 881 listed ransomware victims, and APT28 exploited SOHO routers for DNS hijacking while Iranian groups targeted US industrial control and OT systems.

Help Net Security · 28d agoResearch

Researchers Turn USB Auto-Install Into a Full SYSTEM Takeover on Windows 11

DEF CON researchers chained Windows Plug and Play auto-install abuse with third-party driver flaws to reach SYSTEM on fully updated Windows 11.

In 'Plug And Pwn' research prepared for DEF CON 34, Alejandro Hernando and Borja Martinez emulated USB devices so Windows auto-installed signed vendor software, chaining a Sierra Wireless SwiService.exe SetDNS primitive, a Sony FeliCa co-installer path-traversal flaw that writes a DLL into System32, and device reconnection for SYSTEM code execution. A remote variant over Remote Desktop forges a synthetic Intel RealSense device and abuses a CRYPTBASE.dll search-order hijack when PnP or low-level USB redirection is enabled. Microsoft notes RDP does not allow supported PnP and RemoteFX USB redirection by default, and no in-the-wild exploitation has been reported.

The Hacker News · Aug 11, 2026Research