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CVE-2026-16028: Protocol::HTTP2 versions before 1.14 for Perl allow memory exhaustion via closed streams that stream_state never removes from the connection stream table

CVE-2026-16028: Protocol::HTTP2 Perl library before 1.14 lets closed streams linger in the connection table, enabling remote memory exhaustion.

Protocol::HTTP2 versions before 1.14 for Perl allow memory exhaustion because closed streams are never removed from the connection stream table by stream_state. The flaw was disclosed on oss-security by Robert Rothenberg on September 7, 2026. Users should upgrade to Protocol-HTTP2 1.14 or later on CPAN.

oss-security · 8d agoVulnerabilityCVE-2026-16028

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 · 26d agoResearch

USN-8571-2: Apache HTTP Server regression

Ubuntu issues USN-8571-2 fixing an Apache HTTP Server regression that prevented startup when HTTP/2 proxying was enabled.

Ubuntu released USN-8571-2 to fix a regression introduced by USN-8571-1 in Apache HTTP Server. The earlier fix was incomplete due to a missing library symbol, causing Apache to fail to start when HTTP/2 proxying was enabled. The original advisory addressed CVE-2026-33007, a memory-handling flaw in mod_authn_socache allowing remote denial of service, and an HTTP response splitting vulnerability affecting multiple modules, credited to Pavel Kohout, Arkadi Vainbrand, Haruki Oyama, Merih Mengisteab, and Dawit Jeong.

Ubuntu Security Noticesupdated · 4d agofirst · 5d agoAdvisory 13 sourcesCVE-2026-33007

Understanding the Privacy-Preserving Potential of HTTP/2 Against Webpage Fingerprinting

Researchers show HTTP/2 features can emulate website fingerprinting defenses like FRONT and Tamaraw with tunable privacy-overhead trade-offs.

An arXiv paper demonstrates that application-layer defenses such as HTTPOS, LLaMA, FRONT, ALPaCA, and Tamaraw can be emulated through HTTP/2 features at both the client and server side, including proactive resource suggestion, multiplexing, and flow control. The authors propose a unified evaluation blueprint that calibrates defense parameters per dataset, combines practical attacks with information-theoretic leakage estimators, and measures overheads to map each defense's privacy-overhead trade-offs.

arXiv cs.CR · 11d agoResearch

VU#308749: Remote Code Execution and Arbitrary File Read Vulnerabilities in Kaltura Servers

Insecure deserialization in Kaltura's legacy HTML5 Player V2 (mwEmbed) allows arbitrary file read and remote code execution; Player V7 is unaffected.

CERT/CC issued VU#308749 for two flaws in Kaltura's HTML5 Player V2 library (mwEmbed/html5lib), both caused by the same insecure deserialization bug. The flaws enable arbitrary file read and remote code execution via the exposed mwEmbedLoader.php endpoint. Affected versions include html5lib v2.45, v2.103 and earlier, and other v2.x releases; the currently supported Player V7 is unaffected. No evidence of exploitation was cited.

CERT/CC Vulnerability Notes · 21d agoVulnerability

Kimwolf v7 Android Botnet Makes HTTP/2 DDoS Traffic Look Like Legitimate Browsing

New Kimwolf v7 Android botnet adds HTTP/2 DDoS floods with Chrome fingerprints and takedown-resistant ENS/Tor C2.

Palo Alto Networks Unit 42 discovered Kimwolf v7, an evolution of the Kimwolf/AISURU Android and IoT botnet first tracked in February 2026. The new version performs HTTP/2 floods mimicking Chrome browser fingerprints and uses Ethereum Name Service, Tor hidden services, and a local proxy for resilient C2. The botnet targets Android TV boxes via ADB on port 5555 and offloads propagation to an external loader.

The Hacker News · Aug 15, 2026Malware in the wildCVE-2024-36401

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 · 29d agoResearch

Advanced URL Filtering Archives

Palo Alto Networks markets Advanced URL Filtering as combining a malicious URL database with real-time ML and DL web protection.

The Unit 42 blog page is a product category archive for Advanced URL Filtering. The product description states it combines a malicious URL database with a real-time web protection engine powered by machine learning and deep learning models. No research findings, incidents, or vulnerabilities are discussed.

Palo Alto Unit 42 · 7d agoIndustry 6 sources

'HTTP Terminator' Hunts for Novel Desync Attacks

PortSwigger's James Kettle discusses HTTP Terminator, an AI-powered open source tool that uncovered new HTTP request-smuggling (desync) techniques.

PortSwigger researcher James Kettle spoke with Dark Reading about HTTP Terminator, an AI-powered open source tool built to hunt for novel HTTP desync vulnerabilities. The tool has already discovered new HTTP request-smuggling techniques, extending Kettle's prior desync research.

Dark Reading · 20d agoTools

Trends in Web Threats: Old Web Skimmer Still Active Today

Unit 42 detected 577,000 landing URL incidents in Q1 2022, with an old web skimmer family still actively stealing payment card data.

Palo Alto Unit 42 detected 577,275 landing URL incidents (116,643 unique) and 2,043,862 malicious host URL incidents (180,370 unique) between January and March 2022. Web threat volumes declined after the November 2021 holiday peak, but an old web skimmer family remained active. Business and economy sites overtook personal sites as the most common apparently benign entry points. Most malicious domains geolocated to the United States, Germany, and Russia, though proxy servers and VPNs obscure true locations.

Palo Alto Unit 42 · 29d agoResearch

From Parameters to Answers: How LLMs Retrieve and Use Their Internal Knowledge

Interpretability study traces how Qwen, Llama, and Gemma route query information and internal knowledge across layers when answering questions.

Researchers used layerwise interventions on hidden states to separate query-routing signals from target knowledge in language models, testing Qwen, Llama, and Gemma on country-continent questions with varied answer types. A pair-conditioned request direction strengthens before interventions alter downstream knowledge, opening a causal window while answer-supporting content is still forming. Trajectories differ by model: Gemma shows a partially overlapping mid-layer routing profile, while Llama has no sustained routing-effect window under the same gates.

arXiv cs.AI / cs.LG / cs.CL · 5d agoAI research1

HTTP/2 Bomb CVE-2026-49975

Fortinet advisory details CVE-2026-49975, an Apache HTTP Server HTTP/2 flaw enabling denial of service, affecting versions 2.4.17 through 2.4.67.

Fortinet PSIRT advisory FG-IR-26-163, revised 2026-08-19, covers CVE-2026-49975, a memory allocation with excessive size value flaw (HTTP/2 bomb) in Apache HTTP Server's mod_http2, scored CVSSv3 5.8. Malicious HTTP requests can cause a denial of service, and affected versions span Apache HTTP Server 2.4.17 through 2.4.67. The advisory text does not state which Fortinet product bundles the affected Apache component or whether exploitation has been observed.

Fortinet PSIRT · Aug 12, 2026AdvisoryCVE-2026-49975

wp2shell: incident response guide (CVE-2026-63030 + CVE-2026-60137)

Eye Security published forensic IR tooling for wp2shell (CVE-2026-63030/CVE-2026-60137), the unauthenticated WordPress core RCE chain, after WordPress.org forced auto-updates.

wp2shell chains a REST API batch-endpoint route-confusion bug (CVE-2026-63030) with an SQL injection in WP_Query's author__not_in parameter (CVE-2026-60137), giving unauthenticated attackers rogue admin and code execution on default installs. Adam Kues of Searchlight Cyber discovered the flaw, a public PoC exists on GitHub, and WordPress.org forced automatic updates across an estimated 200M+ sites. Eye Security released a compromise-scanner WordPress plugin and browser extension and notes database artifacts (oEmbed cache rows, changesets) are the primary evidence since the attack is log-blind; fixed versions are 6.8.6, 6.9.5, and 7.0.2.

PEEP Turns Chrome and Edge Into Post-Compromise Backdoors for Host Command Execution

SOCRadar disclosed PEEP, a post-exploitation Chromium extension toolkit that turns Chrome and Edge into host-level backdoors via native messaging and C2 polling.

SOCRadar researchers detailed PEEP, a Chromium-based post-exploitation toolkit masquerading as a 'Smart Bookmarks' extension injected directly into Chrome and Edge profiles by forging Secure Preferences integrity values, bypassing Web Store checks. A native-messaging host binary (nm_host.exe) extends the browser agent to host-level command execution, file management, credential theft, and session hijacking, while the extension polls C2 endpoints at 206.237.30.232 or xfjcc.fun every 30 seconds over plaintext HTTP and exfiltrates browsing history, cookies, and tab metadata. PEEP is derived from the open-source RedExt red teaming framework, adds PowerShell persistence scripts, and includes a Linux-targeting Python script, suggesting cross-platform intent. The activity is unattributed but contains Chinese-language artifacts; a C2 /health endpoint showed 34 agent entries and 10 active sessions.

The Hacker News · 8d agoMalware in the wild

New IoT Malware Uses Public Linux Exploits to Gain Root and Launch DDoS Attacks

Nozomi details KATARU, an IoT botnet that brute-forces Telnet, exploits public Linux kernel flaws for root access, and launches multi-protocol DDoS attacks.

KATARU, discovered after honeypot Telnet brute-force activity from a Vietnamese IP, downloads an ARM payload (vlxx.arm) and attempts privilege escalation by editing /etc/passwd or exploiting CVE-2026-46300 (Fragnesia), CVE-2026-43284 (Dirty Frag), and CVE-2026-31431 (Copy Fail). It combines Mirai-style TCP, UDP, ICMP, HTTP, QUIC and DNS floods with application attacks against Minecraft, FiveM, OpenVPN and WireGuard. The malware uses X25519 and ChaCha20-Poly1305 encrypted C2, unusually broad persistence across systemd, cron, init frameworks, and Android hooks, plus anti-debugging and decoy traffic to hinder analysis. Implementers copied x86 shellcode into the ARM binary and reused an RFC 7748 test-vector key, indicating low-quality but rapidly evolving commodity development.

GBHackersupdated · 4d agofirst · 4d agoMalware in the wild 2 sourcesCVE-2026-46300CVE-2026-43284CVE-2026-31431

Building Multilingual Bridges: Data Mixing as the Pillar of Generalization for In-Language Reasoning

Tiny Aya L2-Thinker, a 3.35B model, achieves over 93 percent in-language reasoning across 60 languages via optimized multilingual data mixing; weights released.

The paper studies L2 reasoning, the ability to reason consistently in the language of the user's prompt, approached through SFT data composition and scheduling. Tiny Aya L2-Thinker (3.35B) achieves an in-language reasoning rate above 93 percent across 60 languages on six benchmarks spanning math, commonsense, instruction following, open-ended generation, and cultural reasoning. Findings show generalization to held-out languages comes from broader language coverage, multilingual non-reasoning data, and a strong English reasoning backbone, suggesting reasoning is language-agnostic and transferable without per-language supervision. Model weights and multilingual reasoning data are publicly released.

arXiv cs.AI / cs.LG / cs.CL · 6d agoAI research1

PEEP: A Browser RAT Posing as a Chrome Extension

SOCRadar's STRU analyzed PEEP, an emerging Chromium-based RAT disguised as a Chrome extension enabling post-exploitation control of browsers.

SOCRadar's Threat Research Unit (STRU) identified and analyzed PEEP, a Chromium-based post-exploitation toolkit distributed as a browser extension. PEEP provides RAT-style capabilities while posing as a legitimate Chrome extension. It is assessed as an emerging threat worth monitoring by defenders.

SOCRadar · 11d agoMalware

Climate-ModernBERT: Revisiting Corpus Composition for Domain-Adaptive Continued Pretraining

Climate-ModernBERT domain-adapted encoders reach 76.3 average F1 across nine climate benchmarks, 2.8 points above vanilla ModernBERT-Base.

The authors continue pretraining ModernBERT-Base on three climate corpora - academic text, climate-filtered web data, and synthetic documents - and compare joint mixtures against parameter-space merging of specialized checkpoints. The best model achieves 76.3 average F1 across nine climate NLP benchmarks, a 2.8-point improvement over the vanilla baseline. Academic climate corpora provide the strongest adaptation signal, and parameter-space merging outperforms joint multi-source training while preserving complementary corpus information; all variants are released.

arXiv cs.AI / cs.LG / cs.CL · 8d agoAI research

rosbridge_library Protocol.incoming() quadratic CPU cost in JSON fallback

rosbridge_library's Protocol.incoming() has quadratic CPU cost in its JSON fallback, enabling denial of service via crafted messages.

Evgenios Gkritsis disclosed an algorithmic-complexity defect in rosbridge_suite's rosbridge_library Protocol.incoming() JSON fallback path, classified as CWE-407/CWE-1050. The flaw exists in the current ros2 branch and was not removed by PR #1199, having been present since the fallback was introduced. Crafted input can drive quadratic CPU cost and cause denial of service.

oss-securityupdated · 1d agofirst · 1d agoVulnerability 3 sources1

Telegram Desktop Flaw Could Turn Old Chat Exports Into Data Theft Traps

ExPatch disclosed stored XSS in Telegram Desktop HTML export letting bot messages steal chat data when exports open in browsers.

ExPatch researchers Denis and Aleksander Rostilov found a stored XSS flaw (CVSS 8.2) where bot inline keyboard button text was written unescaped into HTML chat exports, executing attacker JavaScript in browsers. The payload can persist in chat history for months, exfiltrate messages, metadata, and local file paths, and rewrite the page, spreading via forwarded messages without bot membership. Telegram fixed it by applying SerializeString(), first stable fixed release 7.0.1 shipped July 14, 2026, but HTML exports created with vulnerable versions remain dangerous.

Security Affairs · 20h agoVulnerability1· 1 read

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 · 5d agoResearch

ZDI-26-590: libwebsockets HTTP/2 HPACK Path Header Parsing Out-Of-Bounds Write Remote Code Execution Vulnerability

ZDI disclosed CVE-2026-19773, an unauthenticated out-of-bounds write allowing remote code execution in libwebsockets HTTP/2 HPACK parsing, rated CVSS 9.8.

The Zero Day Initiative published advisory ZDI-26-590 for an out-of-bounds write vulnerability in libwebsockets' HTTP/2 HPACK path header parsing. A remote attacker can execute arbitrary code on affected installations without authentication. The flaw is tracked as CVE-2026-19773 and carries a CVSS score of 9.8.

You Get What You Sample: Evaluating Sampling Strategies for Web Security Measurements

Evaluation of 500k Tranco and 24.8M Common Crawl hosts shows Top-N domain sampling biases web security measurements; probability sampling yields unbiased estimates.

The study is the first comprehensive investigation of how sampling strategies affect web security measurement conclusions, comparing datasets and strategies across 500k Tranco domains and 24.8M Common Crawl hosts. It shows Top-N selection does not reflect the overall web distribution and may bias observed vulnerability rates, while probability-based strategies yield stable, unbiased prevalence and impact estimates. Hybrid sampling offers no advantage because its deterministic prefix consistently hurts accuracy, and the authors propose an adaptive probability-based strategy effective even when target prevalence is unknown.

arXiv cs.CR · 5d agoResearch1

Molecular Déjà Vu: Digit-Level Retrieval of Published Values in Frontier Language Models

Audit of 22 frontier models finds widespread verbatim retrieval of published molecular property values, with higher reasoning increasing recall of memorized numbers.

An arXiv audit tests 22 frontier LLMs across 12 molecular regression benchmarks for verbatim retrieval of published values. More than 50% of the LLMs show verbatim retrieval on five datasets, and identical experiments are flagged 89% more often at a high reasoning level than at the lowest one. Suppressing retrieval moves model prediction errors closer together in relative terms, suggesting predictive capability is not determined solely by memorized values.

arXiv cs.AI / cs.LG / cs.CL · 11d agoAI research1

Atlas: Efficient Verifiable Semantic Search

Atlas delivers zero-knowledge proofs for HNSW semantic search, verifying RAG retrieval in under a second on SIFT1M and 2.0 seconds at 100M vectors.

Atlas lets a search provider prove that a query was answered correctly against a committed HNSW index without revealing the index, addressing provider deviations like truncation or bias. It combines offline preprocessing, a fixed-size-state restructuring of HNSW with a correctness proof, and timestep-tagged batching of per-step arguments. The system proves queries in under a second on SIFT1M and 2.0 seconds at 100 million vectors while preserving plaintext HNSW recall, and proven retrieval maintains end-to-end RAG answer quality at lower cost than prior verifiable retrieval systems.

arXiv cs.CR · 5d agoResearch1

USN-8749-1: CivetWeb vulnerabilities

Ubuntu USN-8749-1 patches CivetWeb URI and HTTP request parsing flaws enabling remote DoS or possible code execution.

Ubuntu Security Notice USN-8749-1 addresses two CivetWeb vulnerabilities. CVE-2025-55763 involves incorrect URI parsing that could allow a remote attacker to cause denial of service or execute arbitrary code, affecting Ubuntu 22.04 LTS and 24.04 LTS. CVE-2025-9648 involves incorrect HTTP request parsing enabling remote denial of service.

Google’s new search redirects make links harder to check before you click

Google routes some search result links through encoded google.com/goto?url= redirects, breaking hover-to-verify link checks and raising scraping costs.

Google has started routing some search result links through opaque google.com/goto?url=... redirects using a custom Google-specific encoding, with the destination visible only via the redirect response's Location header. Google confirmed the rollout as an anti-abuse measure, most likely to make bulk extraction of destination URLs from search results more difficult and costly. Malwarebytes warns the change undermines the standard hover-before-clicking safety advice, while legitimate rank-tracking, SEO auditing, archival, and accessibility tools now face the same rate limits and costs as abusive scrapers.

Malwarebytes Labs · 1d agoIndustry

USN-8762-1: polkit vulnerability

Ubuntu warns polkit mishandles cookie input, letting a local attacker crash the daemon or possibly execute arbitrary code.

Ubuntu Security Notice USN-8762-1 addresses a vulnerability in polkit stemming from incorrect handling of cookie input. A local attacker could exploit the flaw to cause polkit to crash, producing a denial of service, or potentially execute arbitrary code. The notice indicates exploitation requires local access to the affected system.

Ubuntu Security Notices · 13h agoAdvisory