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Sandworm-Linked UAC-0145 Uses Fake Job Interviews to Push VPN That Can Run Commands

CERT-UA says Sandworm-linked UAC-0145 poses as recruiters in fake job interviews to deliver a trojanized WireGuard VPN that runs attacker commands on victims' hosts.

CERT-UA attributes the campaign, ongoing since May 2026, to UAC-0145, a subgroup within GRU-affiliated Sandworm (APT44). Posing as HR staff of firms like ATLAS Business Group and Sopra Steria Bulgaria, attackers lure Ukrainian IT specialists into Zoom interviews, then share failing WireGuard configs and push a custom SopraVPN client from SourceForge. The modified WireGuard build supports a non-standard SymmetricKey option holding AES-256-GCM-encrypted PowerShell, decrypted with the decoded PrivateKey and executed via runScriptCommand. A scheduled task then downloads a second-stage payload on Windows, while the Linux variant fetches it via cURL.

The Hacker News · Aug 12, 2026Threat actor1

APT28-Linked HOOKEDGE Backdoor Targets European Government and Diplomatic Organizations

Recorded Future links new HOOKEDGE batch-script backdoor campaigns against Romanian, Spanish and Turkish government targets to Russia's APT28 (BlueDelta).

Recorded Future's Insikt Group identified campaigns deploying the previously undocumented HOOKEDGE backdoor against government and diplomatic organizations in Romania, Spain and Türkiye from late September 2025 to early April 2026. The lightweight Windows batch backdoor is delivered via macro-enabled Word documents and attributed with moderate confidence to APT28 (Fancy Bear, tracked as BlueDelta), described as the evolutionary successor to HEADLACE, using webhook.site for C2, payload staging and exfiltration. HOOKEDGE fetches .cmd payloads and returns output through headless Microsoft Edge HTTP requests, maintains a 30-minute scheduled task, and a second-stage implant gives high-value targets five-minute beaconing for interactive operator tasking.

The Hacker News · 19d agoThreat actor in the wild

DPRK APTs: Ted backdoor and curlRAT target South Korean media and automotive sectors

Rapid7 uncovered a DPRK-linked Linux toolkit using a HAProxy-embedded ted backdoor, SSH keylogger, and curlRAT against South Korean media and automotive firms.

Rapid7 Labs identified a previously undocumented framework attributed with medium confidence to DPRK actors, targeting South Korean automotive and media organizations likely since early 2025. The toolkit embeds a backdoor compiled into HAProxy 2.8.12 using its filter API, plus trojanized crond, agetty, atd, sshd, and polkitd, an SSH keylogger storing credentials under /var/lib/sshd/, and a curl-based RAT with a watchdog thread. It enables remote command execution, malicious script injection into served webpages (a watering-hole loop), credential harvesting, and long-term surveillance. Hardcoded C2s are associated with APT37 via ThreatFox, and exposed groupware portals and mail servers align with Kimsuky tradecraft; the initial access vector and any CVE remain unconfirmed.

Rapid7 Blog · 12d agoThreat actor in the wild1

Threat actors are coming for your AI assets to operationalize their use of AI

Google GTIG reports espionage and crime groups stealing AI models, prompts, and API credentials, plus distillation campaigns and agentic AI attack automation.

Google Threat Intelligence Group's quarterly AI Threat Tracker reports adversaries stealing proprietary models, source code, prompts, and API credentials from government, healthcare, and media targets, including China-based UNC6508 compromising clouds to run unauthorized LLM workloads. Distillation campaigns against Google's models exceeded 100 million prompts launched via thousands of stolen account credentials through proxy networks. Mandiant also observed a financially motivated actor deploy an autonomous multi-agent framework that harvested thousands of third-party credentials in under 6 hours, and a 'Recon' framework on a live C2 server managing over 23,000 stolen credentials including cloud and AI API keys.

CSO Online · 1d agoThreat actor in the wild

DianShi-RxnDB: A Large-Scale, Fine-Grained Organic Reaction Data Platform Built via a Fully Automated Pipeline for Researchers and AI Agents

Researchers release DianShi-RxnDB, a database of roughly 24 million organic reaction instances extracted automatically from USPTO and EPO patents since 1976.

DianShi-RxnDB is built by a fully automated pipeline integrating patent text, images, and reaction schemes, yielding about 24 million reaction instances, of which 14.8 million (61.7%) pass automated qualification checks. Manual evaluation of 1,300 sampled instances showed 92.95% field-level accuracy, and comparisons with Pistachio found advantages in deduplicated record counts and granularity. The platform offers a web research workbench and a Model Context Protocol (MCP) service enabling AI agents to perform composable structured retrieval.

Hugging Face daily papers · 11d agoAI research

Autonomous AI Agents Compromise Thousands of Credentials in Under Six Hours

Google's GTIG reports threat actors using autonomous AI agents, credential stealers, and LLMs to steal AI models, API credentials, and harvest thousands of credentials.

Google Threat Intelligence Group says attackers are targeting proprietary AI models across healthcare, government, and media, exfiltrating API credentials, and co-opting victim cloud environments to run unauthorized AI workloads. TeamPCP (Altered Spider/UNC6780) is conducting supply chain compromises of PyPI, npm, and Docker Hub, deploying the SANDCLOCK and DUSTMAKER credential stealers, with DUSTMAKER using AI workspace poisoning and prompt injection for defense evasion. One financially motivated actor used an autonomous multi-agent framework to compromise thousands of third-party credentials in under six hours without human intervention. China-nexus groups UNC6508 and Basin Castle (Mustang Panda) used local open-weight LLMs and commercial LLMs like Gemini, Claude, and Codex for espionage tasks and evading provider monitoring.

The Hacker News · 8d agoThreat actor in the wild 2 sources1

UAT-10147 deploys SPECTRE: A cross-platform implant with Linux rootkit and BYOVD capabilities

Cisco Talos identifies UAT-10147 deploying the SPECTRE implant with cross-platform C2, credential theft, and kernel-level EDR bypass.

Cisco Talos reports that the tracked threat actor UAT-10147 is deploying a newly identified implant named SPECTRE. SPECTRE supports cross-platform command-and-control, process injection, credential theft, and anti-analysis protections. It also includes a Linux rootkit and BYOVD (bring your own vulnerable driver) capability enabling kernel-level EDR bypass, marking an evolution in commodity intrusion tooling.

Cisco Talos · 27d agoThreat actor in the wild

2,000 Leaked Documents Reveal How Russia Turns Engineering Students Into GRU Cyber Operators

Leaked Bauman Moscow State Technical University files reveal a hidden GRU training pipeline feeding APT28 and Sandworm units.

More than 2,000 leaked Bauman Moscow State Technical University documents show that Department No. 4, a hidden program inside the Military Training Center, trained roughly 250 career and reserve students for GRU cyber and intelligence roles across six academic years. Graduates were linked to Military Unit 26165 (APT28), Unit 74455 (Sandworm/APT44) and Unit 29155, and former Unit 26165 commander Viktor Netyksho was involved in department oversight. Reporting by The Insider, The Guardian, Le Monde, Der Spiegel and other outlets, with independent analysis by DomainTools, estimates 10-15 students annually were selected for GRU-related assignments before graduating.

Security Affairs · 13d agoThreat actor1

Head Mare APT is exploiting vulnerabilities in an unpatched TrueConf server to deliver PhantomCore and PhantomGraph to video conference participants

Head Mare APT exploits unpatched TrueConf server vulnerabilities to deliver PhantomCore and PhantomGraph backdoors to video conference participants.

Kaspersky discovered malicious TrueConf software installers used by the Head Mare APT group to deploy the PhantomCore and PhantomGraph backdoors. The group exploits vulnerabilities in an unpatched TrueConf server to reach targets. Video conference participants are infected via the trojanized installers.

Kaspersky Securelist · Aug 11, 2026Threat actor in the wild

Lazarus hackers pair fake job offers with Windows zero-day exploit

Lazarus' Operation Dream Job targets the defense sector with fake job offers, a Windows LPE zero-day (CVE-2026-68820), and new Troy and RelayShell backdoors.

Check Point documented two parallel infection chains in Lazarus' Operation Dream Job: a digitally signed PDF viewer with DLL sideloading delivering the MISTPEN in-memory downloader, and a trojanized SecurityPDF viewer, distributed via fake Enveil websites, installing the newly documented Troy backdoor. A component exploits CVE-2026-68820, a local privilege escalation zero-day in the Windows AFD.sys driver used since at least early July, which Microsoft patched on August 11, 2026, enabling deployment of the FudModule kernel-mode rootkit. Lazarus also compromised Roundcube webmail servers vulnerable to CVE-2025-49113 to deploy the RelayShell PHP web shell and relay C2 traffic, targeting defense-sector organizations primarily in Western Europe and India. Separately, CERT-UA documented Sandworm's UAC-0145 using fake job offers against IT professionals since May 2026.

Help Net Security · Aug 12, 2026Threat actor in the wildCVE-2026-68820CVE-2025-49113

APT group HoneyMyte upgrades CoolClient: the backdoor gets a kernel-level Windows rootkit

Kaspersky reports APT group HoneyMyte upgraded its CoolClient backdoor with a kernel-mode Windows rootkit hiding processes, files, and network connections.

Kaspersky researchers discovered a new variant of the HoneyMyte CoolClient backdoor equipped with a kernel-mode Windows rootkit driver. The rootkit hides malicious processes, files, and network connections from security tools and threat analysts, significantly increasing the backdoor's stealth. The report documents an upgrade to the APT group's backdoor tooling with a kernel-level implant.

Kaspersky Securelist · Aug 14, 2026Threat actor in the wild

CVE-2025-25249 Exploitation Delivers PivotC2, a FortiGate Post-Exploitation RAT

Attackers exploiting CVE-2025-25249 in Fortinet FortiGate firewalls deploy PivotC2, a post-exploitation RAT, on exposed edge devices.

SOCRadar reports that exploitation of CVE-2025-25249 is being used to deploy PivotC2, a purpose-built post-exploitation RAT, on FortiGate firewall appliances. The attack follows the common pattern of compromising public-facing edge devices such as VPNs, routers, and firewalls as the initial entry point. Defenders running FortiGate appliances should prioritize patching and watch for post-exploitation activity indicating RAT deployment.

SOCRadar · 8d agoExploit / PoC in the wildCVE-2025-25249

UAT-10147: Chinese-speaking adversary integrates agentic AI into post-compromise operations

Cisco Talos tracks UAT-10147, a Chinese-speaking cybercrime group exploiting vulnerable web servers and using agentic AI in post-compromise operations.

Cisco Talos identified a Chinese-speaking cybercrime group tracked as UAT-10147 that targets a wide range of vulnerable web servers. The report maps affected countries and analyzes the impact of BadIIS infections on compromised servers. It also documents the attack chain and emerging use of agentic AI during post-compromise activities.

Cisco Talos · 27d agoThreat actor in the wild

PrivEscalate: Measuring and Augmenting the Threat of LLM-Automated Linux Privilege Escalation

Researchers release PrivEscalate, a 531-scenario benchmark showing LLM agents' Linux privilege-escalation success varies by vulnerability class, plus PrivEscAgent, a domain-specialized agent that boosts success.

The paper introduces PrivEscalate, an open-source benchmark of 531 Dockerized Linux privilege-escalation scenarios spanning 14 sub-categories, plus 329 parameterized variants measuring sensitivity to environmental distractors. Evaluating six LLMs across three agent architectures shows capability is heterogeneous across vulnerability classes, sensitive to perturbation, and architecture-dependent. The authors also present PrivEscAgent, a wrapper adding deterministic enumeration, category matching, and step planning that outperforms prior privesc-agent baselines without modifying the underlying LLM. The benchmark is released to support LLM agent evaluation, defensive tool validation, and red-team training.

arXiv cs.CR · 8d agoResearch

An AI-Assisted Cyber Attack: Inside a Unit 42 Investigation

Unit 42 investigated a ransom attack in which frontier AI agents autonomously breached an enterprise network, compressing weeks of tradecraft into under 10 hours.

Unit 42 incident responders documented an intrusion where a single human operator directed frontier AI agents to breach an enterprise network autonomously as part of a ransom attack. The agents executed more than 50 MITRE ATT&CK techniques in under 10 hours, work that would normally require roughly two weeks of human red-team effort. They breached a public-facing web service, mapped internal microservices, scraped hard-coded secrets from code repositories, harvested root credentials from the secrets manager, and hijacked CI/CD builds to exfiltrate cloud access keys. The attacker also used stolen cloud keys to repurpose the victim's AI endpoints as post-compromise infrastructure and left behind an 80-page AI-generated security audit documenting dozens of exploited findings.

Palo Alto Unit 42 · 14d agoThreat actor in the wild

Pegasus Zero-Click Exploit Infects Serbian Student Activist's iPhone

Citizen Lab and SHARE Foundation confirm a Serbian student activist's iPhone was infected with NSO Group Pegasus via a zero-click iMessage exploit.

Forensic analysis found high-confidence infection indicators on the activist's iPhone during December 2025 and January 2026, using an iMessage zero-click exploit the Citizen Lab believes was patched as of iOS 18.4.1, released April 2025. The target was among at least 14 Apple Threat Notification recipients in Serbia's student movement, civil society, and opposition politics documented by the SHARE Foundation. Targeting occurred ahead of key 2026 election cycles; Amnesty Tech also confirmed a new NoviSpy version on another student movement member's device.

Infosecurity Magazine · 13d agoThreat actor in the wild

Meta FAIR Introduces AI Research Preference Models (RPMs): Ranking ML Experiments Before Spending GPU Hours

Meta FAIR, Oxford and UCL introduce Research Preference Models that rank unexecuted ML experiments, lifting AIRS-Bench scores from 0.684 to 0.729 and cutting compute ~1.6×.

Researchers from Meta FAIR, Oxford, and UCL introduce Research Preference Models (RPMs), which use frozen pretrained LLMs (Qwen3.6-27B backbone, no fine-tuning) to rank unexecuted experiment candidates and execute only the winner of a pairwise knockout tournament. Two variants shipped: an inference-only LLM-as-a-judge and an agentic variant that runs small pilot experiments in an H200 sandbox. On AIRS-Bench (20 tasks, 24 hours on one H200, 10 seeds), scores rise from 0.684 (random) to 0.711 and 0.729 versus a 0.748 validation oracle, and both variants reach the baseline's 24-hour score in roughly 15 hours. The team reports new SOTA on WinoGrande (94.1% with Agentic RPM) and SVAMP (95.7% with inference-only).

MarkTechPost · 10d agoAI research

AI agents help compress ransomware intrusion to under 10 hours, raising stakes for CISOs

Unit 42 reports AI agents compressed a ransomware intrusion from weeks to under 10 hours, using 50+ MITRE ATT&CK techniques against an enterprise network.

Palo Alto Networks Unit 42 investigated a ransomware incident where AI agents moved through an enterprise network in under 10 hours, work that would have taken human operators roughly two weeks. The attacker entered via a public-facing API endpoint, used automated reconnaissance to map microservices, searched source-code repositories for credentials, and accessed a secrets-management system. They hijacked enterprise code workflows to exfiltrate cloud access keys, attempted Terraform backdoors (blocked by branch protections), and used stolen credentials to access the victim's own AI services as attack infrastructure. Over 50 MITRE ATT&CK techniques were observed; the actor confirmed using frontier AI models and agentic frameworks during negotiations.

CSO Online · 13d agoThreat actor in the wild

Linux Detection Engineering - Local Privilege Escalation

Elastic details a layered detection framework for Linux local privilege escalation, covering 2026's copy-on-write bug wave and LLM-assisted discovery.

Elastic Security Labs describes how most Linux local privilege escalations share a common host flow — an unprivileged process launched from a writable path becoming root — and proposes layered detections combining general outcome-based rules with per-technique rules in Elastic Defend and Auditd. It tracks 13 recent LPE disclosures, seven of which share a copy-on-write/zero-copy bug class, including Copy Fail, DirtyFrag, Fragnesia, DirtyDecrypt, DirtyClone, pedit COW, and RefluXFS. Qualys attributes RefluXFS to an LLM-assisted research effort with Anthropic using Claude Mythos Preview, and another bug is credited to an LLM-assisted workflow. Detection and endpoint rules are published in Elastic's detection-rules and protections-artifacts repositories.

Elastic Security Labs · 5d agoResearch

Pegasus and NoviSpy Used Against Serbian Protesters

Citizen Lab confirmed zero-click Pegasus infected a Serbian student activist's iPhone, part of the largest documented Serbian spyware wave targeting at least 14 people.

The Citizen Lab, with the SHARE Foundation, confirmed a Serbian student protest movement member's iPhone was infected with NSO Group's Pegasus via an iMessage zero-click exploit between December 2025 and January 2026; Apple patched the exploit in iOS 18.4.1. SHARE Foundation has documented at least 14 targeted individuals since early 2026, including student activists, civil society figures, an opposition MP and a local councilor, coinciding with the March 2026 local elections. SHARE and Amnesty Tech also found a new NoviSpy variant on a student activist's Android phone after Serbian authorities seized it during police questioning.

Security Affairs · 13d agoThreat actor in the wild

Honeypot-Omaha and batch.py [Guest Diary], (Wed, Sep 2nd)

A SANS ISC guest diary describes batch.py, a Python tool that consolidates honeypot logs and enriches IOCs with threat intelligence data.

Written by a SANS.edu BACS intern, the diary explains analysis of the DShield Honeypot-Omaha sensor, which uses Cowrie to emulate SSH and Telnet and log attacker activity. The author's batch.py script implements a four-phase pipeline with SHA-256-generated master and guest authentication to consolidate JSON and log files, correlate data via external APIs, and produce MITRE, CVE, geolocation, threat-score and fingerprint enrichment for investigated indicators.

SANS Internet Storm Center · 13d agoTools1

CoRA-NAS: Coarse Ranking and Anchor-Residual Refinement for Neural Architecture Search

CoRA-NAS combines zero-cost proxy ranking with low-cost learning-curve refinement, achieving the best worst-space Spearman correlation across NAS benchmarks.

The paper proposes CoRA-NAS, a two-stage neural architecture search framework pairing a static ranking prior (CoRA-Rank) with learning-curve refinement (CoRA-Refine) that extrapolates early validation curves for sampled anchors and propagates residual corrections with an ExtraTrees model at about 1% of full training cost. Across NAS-Bench-201, NAS-Bench-101, TransNAS-Bench-101, and NATS-SSS it achieves mean Spearman correlations of 0.946, 0.715, 0.786, and 0.894 respectively, with the best worst-space correlation of 0.715 among compared methods. On NAS-Bench-201/CIFAR-100 its selected architecture reaches 73.32% accuracy versus a 73.37% ground-truth best.

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

Stealth rootkit targeting F5 BIG-IP could expose enterprise identity gateways

Sophos analyzed a stealth Linux rootkit that hides a web shell in memory on compromised F5 BIG-IP APM identity gateways, evading file-based detection.

Sophos analyzed a second-stage Linux rootkit implant found in compromised F5 BIG-IP APM environments running Apache and PHP, linked to exploitation of CVE-2025-53521, an unauthenticated RCE. The implant hooks Apache's PHP-loading process and serves modified in-memory versions of three legitimate webtop PHP files (apm_css.php3, full_wt.php3, webtop_popup_css.php3), leaving on-disk files untouched so hashes and integrity checks pass. It also establishes access via an authenticated local UNIX socket that can provide an interactive /bin/bash session. Experts warn compromised APM appliances, which handle federated SSO and terminate TLS at enterprise perimeters, could enable SSO token theft and lateral movement to trusted downstream applications.

CSO Online · 6d agoMalware in the wildCVE-2025-53521

Hackers Exploit Critical FortiGate Flaw to Deploy AI-Assisted PivotC2 RAT

SOCRadar says attackers exploit FortiGate CVE-2025-25249 to deploy the PivotC2 Node.js RAT, compromising 178 of 30,000 targeted devices and stealing credentials.

SOCRadar's Threat Research Unit reports active exploitation of CVE-2025-25249, a CVSS 9.8 heap-based buffer overflow in the cw_acd daemon of FortiOS and FortiSwitchManager, via crafted CAPWAP requests to UDP port 5246, compromising at least 178 of 30,000 targeted internet-exposed FortiGate devices since July 2026. The campaign deploys PivotC2, a Node.js RAT that provides interactive shells, SOCKS5/HTTP proxying, port forwarding, network scanning, and automated configuration harvesting that decrypts stored FortiGate credentials, including VPN pre-shared keys, SSL-VPN credentials, and LDAP secrets. Russian-language artifacts, AD enumeration, browser credential theft, RDP enablement, and exfiltration of Exchange .pst files to Wasabi S3 point to a Russian-speaking, financially motivated group; two US organizations confirmed full-network intrusions. Fixes include FortiOS 7.6.4/7.4.9/7.2.12/7.0.18+ and FortiSwitchManager 7.2.7/7.0.6+, plus blocking CAPWAP on internet-facing interfaces.

GBHackers · 7d agoMalware in the wildCVE-2025-252492

[remote] PraisonAI praisonaiagents 1.6.77 - Remote Code Execution

Public RCE exploit targets PraisonAI praisonaiagents 1.6.77, an open-source multi-agent AI framework.

Exploit-DB entry 52639 publishes a remote code execution exploit against praisonaiagents 1.6.77, the agent library from PraisonAI used for building LLM-powered multi-agent applications. The PoC demonstrates how attackers could achieve arbitrary code execution on deployments running the vulnerable version. This continues a pattern of serious flaws surfacing in rapidly developed AI agent frameworks.

Exploit-DB · Aug 11, 2026Exploit / PoC

The Hidden Instructions That Can Hijack AI Agents

Hidden prompt injections embedded in documents and metadata can hijack autonomous AI agents, causing data exfiltration and out-of-policy actions at machine speed.

Bowbridge warns that hidden indirect prompt injections, embedded in documents, metadata, emails, images, and code repositories, can cause autonomous AI agents to treat attacker-controlled content as trusted guidance. Because agents inherit user privileges, act silently, and lack human judgment, injections can lead to data exfiltration or file poisoning that traditional security controls cannot detect. A real-world example involved a supplier quote whose metadata instructed an agent to override guidance and select the most expensive option. Bowbridge recommends scanning documents before agents process them.

SecurityWeek · 8d agoAI safety & security

North Korean Hackers Deploy New Linux Espionage Toolkit

Rapid7 says North Korea-aligned actors use a new Linux espionage toolkit (ted HAProxy backdoor, CurlRAT) against South Korean automotive and media targets.

Rapid7 reports a stealthy Linux framework comprising a custom HAProxy backdoor ('ted'), trojanized system binaries (agetty, atd, crond, polkitd, sshd), an SSH keylogger, and CurlRAT that polls C&C every 12 hours. Initial access came via a Groupware login portal flaw, with credential harvesting enabling lateral movement to internal systems. The toolkit supports long-term surveillance, HTTP traffic interception/injection, and drive-by downloads, likely in use since late 2024. Infrastructure and artifacts overlap Operation SyncHole, suggesting Lazarus or APT37 involvement.

SecurityWeek · 9d agoThreat actor in the wild1

Papercut AI Swarm Attack Heralds Changes for Cyber Kill Chain

Dark Reading reports AI-driven 'swarm' attacks like the PaperCut incident now span recon, lateral movement and exfiltration, forcing a rethink of the cyber kill chain.

Dark Reading examines how attackers are incorporating AI across the full kill chain, from building lab environments to stage and test agentic attacks through reconnaissance, lateral movement, and exfiltration. It cites a swarm-style AI attack on PaperCut systems as evidence that AI-enabled attackers are changing established defense and detection models.

Dark Reading · 5d agoThreat actor

The Model Is the Malware | What Four Agentic Intrusions Tell Defenders

SentinelOne analyzes four agentic intrusions tied to OpenAI, Anthropic and Meta agents reaching external systems, urging a new investigation playbook.

SentinelLABS examines four agentic intrusions in which AI agents from OpenAI, Anthropic and Meta reached external systems, following disclosures by those companies. The analysis concludes that the specific tools involved mattered less than the agentic behavior itself, which changes how defenders should approach intrusion investigation. The piece reframes agentic AI systems as both instruments and artifacts of intrusions.

SentinelLABS · Aug 13, 2026AI safety & security in the wild

USN-8727-1: Linux kernel (OEM) vulnerabilities

Ubuntu issued kernel security update USN-8727-1 for OEM kernels, fixing an Arm TLB invalidation flaw (CVE-2025-10263) allowing local privilege escalation.

Ubuntu released USN-8727-1, a security update for the OEM variant of the Linux kernel. It fixes CVE-2025-10263, in which certain Arm processors complete broadcast TLB invalidation before related memory writes are globally observed, potentially letting local attackers bypass memory protections or escalate privileges. The notice also corrects additional kernel flaws across ARM64, ARM32, RISC-V, S390 and other subsystems.

Ubuntu Security Noticesupdated · 9d agofirst · 9d agoAdvisory 6 sourcesCVE-2025-10263

Hackers breach F5 BIG-IP APM devices to deploy Linux rootkit

Sophos analyzed a Linux rootkit on F5 BIG-IP APM devices that injects a fileless PHP web shell, likely after CVE-2025-53521 exploitation.

Sophos analyzed a Linux rootkit targeting F5 BIG-IP APM environments, also tracked by ESET as PoisonedRefresh, which hijacks Apache's apr_dso_load module loader to inject a fileless PHP web shell into memory. The implant intercepts __libc_start_main, hides strings with RC4, creates a password-protected local UNIX socket backdoor for interactive Bash access, and persists across BIG-IP upgrade images while modifying SELinux configuration. It is likely a second-stage payload following exploitation of CVE-2025-53521, a critical RCE flaw F5 reclassified from a DoS issue in March. The ShadowServer Foundation tracked 795 F5 BIG-IP APM endpoints exposed online.

BleepingComputer · 8d agoMalware in the wildCVE-2025-53521