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Chinese-Speaking Hackers Use Noodle RAT Backdoor to Spy on Windows and Linux Systems

Chinese-speaking actors use cross-platform Noodle RAT backdoor to maintain covert access to Windows and Linux systems across Asia-Pacific.

Noodle RAT (also ANGYREBEL/Nood RAT) has been active since at least mid-2016 and was long misidentified as Gh0st RAT or Rekoobe variants until Trend Micro and Cyberint classified it as a distinct multi-platform family. The Windows build (Win.NOODLERAT) is an in-memory modular shellcode backdoor delivered via MULTIDROP and MICROLOAD loaders, while the Linux build supports reverse shells, SOCKS tunneling, and cron persistence after web shell or public-facing service exploitation. It has appeared in intrusions in Thailand, India, Japan, Malaysia, and Taiwan and is linked to Iron Tiger, Calypso APT, Rocke, and Cloud Snooper campaigns spanning espionage and cybercrime. Recently discovered Linux builders 1.0.1 and 1.0.2 indicate the toolkit remains actively maintained.

GBHackersupdated · 8h agofirst · 10h agoMalware in the wild 2 sources

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

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

macOS 27.0 beta 8 (26A5425a)

Apple seeded macOS 27.0 beta 8 (build 26A5425a) to developers with no security fixes disclosed ahead of the final release.

Apple released macOS 27.0 beta 8, build 26A5425a, through its developer program on August 31, 2026. The listing contains only download links and release notes with no vulnerability or CVE information. It is the eighth beta seed in the macOS 27.0 pre-release cycle.

Apple software releases · 16d agoAdvisory

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

Ubuntu 24.04.5 LTS release patches security bugs across ten flavors

Canonical ships Ubuntu 24.04.5 LTS point release bundling security fixes into fresh install media for desktop, server and nine other flavors.

Canonical released Ubuntu 24.04.5 LTS, a point release for the Noble Numbat series that folds accumulated security corrections and high-severity bug fixes into new installation media. Nine flavors including Kubuntu, Xubuntu, Ubuntu MATE, Ubuntu Studio and Edubuntu also moved to 24.04.5. Existing 22.04 LTS users receive the fixes through the automatic upgrade path at no cost. The release notes name no CVEs or bug IDs, and support timelines still count from the original 24.04 launch date (five years for Desktop/Server/Cloud/Core, three for flavors, extendable with Expanded Security Maintenance).

Help Net Securityupdated · 2h agofirst · 5d agoAdvisory 15 sources

tvOS 27.2 beta (24K5088l)

Apple seeded tvOS 27.2 beta build 24K5088l to developers with no security details disclosed in the release listing.

Apple released tvOS 27.2 beta (build 24K5088l) to developers on September 16, 2026, per its software release listing. The listing contains only download links and a pointer to release notes, with no security content or vulnerability details. It is a routine developer beta with no reported exploitable issues.

Apple software releases · 5h agoAdvisory

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

GNU GRUB 2.14: serial-MMIO lockdown bypass in Canonical-signed gcdx64.efi

Canonical-signed GRUB2 serial command accepts arbitrary MMIO addresses, letting local attackers with grub.cfg control bypass Secure Boot lockdown.

A vulnerability in Canonical's grub-efi-amd64-signed (gcdx64.efi, GRUB 2.14) exposes a serial command that accepts a caller-supplied 64-bit MMIO base address. The lockdown path does not restrict this command even when lockdown=y under UEFI Secure Boot, and the serial implementation does not validate that the requested register span belongs to a real UART rather than ordinary RAM. A local attacker with control of GRUB's boot configuration can abuse this to bypass the Secure Boot lockdown.

oss-security · 3d agoVulnerability2

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

macOS 27.2 beta (26B5086k)

Apple released macOS 27.2 beta build 26B5086k to developers for testing.

Apple has published macOS 27.2 beta build 26B5086k on its developer release portal with downloads and release notes. The notice contains no security advisories or CVE information.

Apple software releases · 5h agoAdvisory

macOS 27.0 RC (26A428)

Apple seeded the macOS 27.0 Release Candidate (build 26A428) to developers ahead of the final public release.

Apple published a Release Candidate build of macOS 27.0, labeled 26A428, on its developer release page. The notice only provides download and release-notes links and includes no security content, CVEs, or threat information. RC builds typically precede the general availability of the final operating system version.

Apple software releases · 7d agoAdvisory

MacSync Stealer: How a Google Search for Claude Led to a macOS Infostealer

Huntress dissects MacSync Stealer, a macOS infostealer delivered through fake Claude Code download pages in Google search results.

Huntress SOC analysts published a reverse-engineering analysis of MacSync Stealer, a macOS infostealer distributed through fraudulent Claude Code download pages surfaced via web searches. Users searching for Anthropic's Claude coding tool are redirected to fake download pages that install the stealer, abusing developer trust in popular AI tooling. The writeup covers the analysis of the sample and its delivery chain.

Huntress · Aug 17, 2026Malware in the wild

Russian APT BlueDelta Uses HOOKEDGE to Target Defense and Diplomatic Organizations

Russian GRU-linked BlueDelta (APT28) deployed HOOKEDGE backdoor via macro Word lures against European governments using webhook.site and Microsoft Edge for stealthy C2.

Recorded Future's Insikt Group documented a BlueDelta (APT28/Fancy Bear/Forest Blizzard) espionage campaign from late September 2025 through early April 2026 targeting government and diplomatic organizations in Romania, Spain and Türkiye. The group delivered HOOKEDGE, a lightweight Windows batch-script backdoor, via macro-enabled Word documents with diplomatic lures, including one impersonating Spain's Ministry of the Presidency after a Spanish-Moldovan meeting. HOOKEDGE uses webhook.site as C2, a scheduled task every 30 minutes that downloads commands through Microsoft Edge, and canary pixels like docopened.jpg to track phishing funnel progress. A second tier with 5-minute check-ins served high-value victims, and beaconing intervals were stretched to 61 minutes to evade sandboxes; code overlap ties HOOKEDGE to BlueDelta's earlier HEADLACE backdoor.

Security Affairs · 19d agoThreat actor in the wild1

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

PoisonedRefresh: A Fileless Linux Rootkit That Injects PHP Web Shells Into F5 BIG-IP APM Server Memory

Sophos details PoisonedRefresh, a fileless Linux rootkit that injects a memory-resident PHP web shell into F5 BIG-IP APM after exploitation of CVE-2025-53521.

On September 8, 2026, SophosLabs published an analysis of Linux/Agnt-IC (dubbed PoisonedRefresh by ESET) found in compromised F5 BIG-IP Access Policy Manager environments. Initial access leverages CVE-2025-53521, an unauthenticated RCE in BIG-IP APM when an access policy is configured on a virtual server; F5 confirmed exploitation and links the activity to cluster c05d5254, while Shadowserver observed 795 exposed vulnerable endpoints. A first stage hidden in a modified umount binary modifies /usr/sbin/httpd and SELinux configuration and embeds itself in BIG-IP upgrade images for persistence. The second-stage ELF intercepts __libc_start_main, hooks apr_dso_load, and injects a PHP web shell into libphp memory via mmap manipulation, leaving no disk artifacts, and exposes a /bin/bash shell via a local UNIX domain socket instead of a TCP port.

Security Affairs · 7d agoMalware in the wildCVE-2025-53521

tvOS 27.0 beta 8 (24J5360a)

Apple seeded tvOS 27.0 beta 8 (build 24J5360a) to developers as the annual fall OS release cycle approaches final builds.

Apple released the eighth beta of tvOS 27.0, build 24J5360a, through its developer program on August 31, 2026. The listing contains only download links and release notes with no disclosed security fixes or CVEs. Beta 8 indicates the pre-release cycle is nearing the stable 27.0 rollout.

Apple software releases · 16d agoAdvisory

cPanel LiteSpeed Web Server Vulnerability Allows Shared Server Users to Gain Root-Level Access

Critical LiteSpeed Enterprise flaw fixed in 6.3.7 lets low-privilege shared-hosting users escalate to root and bypass CageFS.

cPanel issued an urgent advisory for a critical privilege escalation in LiteSpeed Web Server Enterprise versions before 6.3.7, allowing a low-privilege shared-hosting account to gain root-level server control and bypass tenant isolation controls including CloudLinux CageFS. Root access would let attackers access other hosted sites, steal databases and credentials, deploy phishing pages, and install backdoors. Administrators are urged to upgrade to 6.3.7 immediately via lsup.sh and to review privileged account activity, cron jobs, SSH keys, and system binaries; no CVE identifier was published.

Cyber Security News · 1d agoVulnerability

Omarchy: Any User Process Can Escalate to Root

A security write-up details how any user process on the Omarchy Linux setup can escalate privileges to root.

A post on 0xcc.io describes a local privilege escalation issue in Omarchy, the Arch-based Linux configuration, where any user process can escalate to root. The disclosure appears to describe a design-level weakness in the distribution's security model. No CVE identifier is mentioned in the available text.

Lobsters · security · 17d agoVulnerability

ToolHive: The open-source way to run any MCP server securely

Stacklok's open-source ToolHive runs Model Context Protocol servers in isolated containers with per-request identity enforcement, audit logging and a signed registry.

ToolHive, shipped under Apache 2.0, containersizes MCP servers locally via Docker or Podman or in clusters through a Kubernetes operator, applying permissions, network filtering, and secrets management. The platform includes a Registry Server implementing the official MCP Registry API with signing and provenance verification, a Virtual MCP Server gateway with OIDC/OAuth single sign-on and OpenTelemetry traces, and a desktop Portal for one-click installs. The browser-based cloud UI is retired, so the desktop app and CLI are the supported rollout paths.

Help Net Security · 9d agoAI tools & infra1

Hackers deploy Linux rootkit on F5 BIG-IP APM devices, hiding web shell in memory

Sophos analyzed a Linux rootkit, tracked as PoisonedRefresh, on hacked F5 BIG-IP APM devices hiding an in-memory web shell linked to exploited CVE-2025-53521.

Sophos and ESET analyzed an implant (named PoisonedRefresh by ESET) deployed on compromised F5 BIG-IP APM appliances, which serves enterprise, financial, government, and public sector deployments. The second-stage payload intercepts __libc_start_main, hooks Apache's APR module loader (apr_dso_load), RC4-encodes key strings, and rewrites PHP file reads in memory to embed a web shell inside legitimate scripts like apm_css.php3, full_wt.php3, and webtop_popup_css.php3, leaving on-disk files unchanged. A related installer component infects /usr/sbin/httpd, persists across BIG-IP upgrade images, modifies SELinux configuration, and deploys the payload. The malware also creates a Unix domain socket at /run/bigtlog.pipe that hands authenticated local connections to /bin/bash; F5 links the activity to CVE-2025-53521, an unauthenticated RCE in BIG-IP APM already exploited in the wild.

Help Net Security · 7d agoMalware in the wildCVE-2025-535211

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

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

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

USN-8514-2: OpenSSH vulnerability

Ubuntu backports an OpenSSH fix to older LTS releases for an scp flaw enabling setuid file placement and privilege escalation.

USN-8514-2 extends the USN-8514-1 OpenSSH fix to Ubuntu 14.04 LTS, 18.04 LTS, and 20.04 LTS. The flaw stems from incorrect file permission handling when downloading files as root using the legacy scp protocol without the preserve-mode option. An attacker could exploit this to install setuid or setgid files on the system, potentially leading to privilege escalation.

Ubuntu Security Notices · 14h agoVulnerability

An Empirical Security Analysis of Open-Source Software Used in Onboard Satellite Systems

Study of 126 onboard satellite OSS repositories finds 2,827 security findings, 72% medium severity or higher, dominated by memory safety and code quality weaknesses.

Researchers performed an empirical security analysis of 126 public repositories of open-source software used in onboard satellite systems using SBOM generation, software composition analysis, static application security testing, infrastructure-as-code analysis, and secret scanning. After cleaning and deduplication the pipeline produced 2,827 findings, with medium-severity findings accounting for 49% and 72% classified medium or higher. A CWE-based taxonomy mapped all findings to eight weakness families, with Memory Safety and Code Quality dominating, followed by Input Validation and Injection. Project-developed code accounted for 81.4% of findings, though external dependency code remained relevant; findings do not establish mission-specific exploitability.

arXiv cs.CR · 2d agoResearch1