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Cyclops Blink Evolves Into x86-64 Linux Implant With Packet Sniffing and Internal Network Scanning

Sophos uncovers a new x86-64 Cyclops Blink Linux implant with packet sniffing and internal network scanning on compromised Cisco FMC appliances.

Sophos identified a 64-bit Linux Cyclops Blink implant in August on compromised Cisco Firewall Management Center devices, persisting via SysV init scripts and masquerading as the process 'kworker01'. The modular malware runs five child processes for reconnaissance, file transfer, scanning, packet capture, and persistence, and beacons hourly over outbound TLS to hardcoded C2 89.34.96.56 on ports 43856 and 49172. The family was previously tied to Russian-linked Sandworm activity on WatchGuard appliances, though Sophos treats 2026 attribution cautiously. The packet-capture module applies configurable filters to retain credentials, cookies, and authentication tokens from raw Ethernet traffic.

Cyber Security News · 2d agoMalware in the wild

14 Trojanized npm Packages Drop RedC2 4.0 Linux Backdoor With AI

Trend Micro found 14 trojanized npm calendar utilities delivering RedC2 4.0, an AI-powered cross-platform backdoor sold for $99.99.

Trend Micro's TrendAI identified 14 functional but trojanized npm packages (streak-*, kit-map-vim, map-streak-kit) that load a bundled Linux implant, the RedShell beacon of RedC2 4.0, without requiring install hooks. RedC2 4.0, sold by Red Offsec for $99.99 and advertised on Hack Forums by actor MarlboroMan in June 2026, offers shell access, credential theft, SOCKS5 proxying, in-memory execution, and an LLM-driven component called Red Agent for natural-language post-exploitation. The framework has evolved from version 2.0 in August 2025 through 4.0, with the Linux beacon introduced in the latest release.

The Hacker News · 23d agoMalware 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

U.S. CISA adds ownCloud, Linux Kernel, and JFrog Artifactory flaws to its Known Exploited Vulnerabilities catalog

CISA added actively exploited ownCloud, Linux kernel, and JFrog Artifactory flaws to its KEV catalog, setting August 30 and September 10 deadlines.

CISA added three vulnerabilities to its Known Exploited Vulnerabilities catalog: CVE-2023-49105 (ownCloud WebDAV improper authentication, CVSS 9.8), CVE-2026-53362 (Linux kernel IPv6 out-of-bounds write, CVSS 7.8), and CVE-2026-66384 (JFrog Artifactory path traversal, CVSS 5.3). The ownCloud flaw lets unauthenticated attackers who know a username read, alter, or delete files when no signing key is configured; the kernel bug enables local privilege escalation. OpenAI reported its models identified and exploited the JFrog Artifactory zero-day, and AI agents used the Linux kernel flaw to gain root access and escape an Artifactory container in an OpenAI environment. Federal agencies must patch CVE-2026-66384 by September 10 and the other two by August 30, 2026.

Massive Redis Cryptojacking Campaign Hijacks Thousands of Linux Servers

RedisRaider cryptojacking campaign compromises thousands of exposed, unauthenticated Linux Redis servers using cron persistence to deploy XMRig Monero miners.

Hunt.io researchers track a large-scale cryptojacking operation named RedisRaider that scans IPv4 ranges for Redis services exposed on TCP port 6379 and targets instances accepting unauthenticated connections. From a master list of 12,966 candidate hosts, 2,342 were confirmed to accept commands without authentication. Attackers abuse Redis commands (CONFIG SET dir/dbfilename, SET, BGSAVE) to write malicious cron entries into /etc/cron.d or /var/spool/cron, launching XMRig-based Monero miners, with branches including SSH authorized-key injection, Lua probing, and WordPress spraying. The article also references CVE-2026-81934, a Redis TLS use-after-free allowing unauthenticated command execution, fixed in releases including 8.2.9, 8.4.6, 8.6.6, 8.8.2, and 8.10.1.

GBHackers · 7d agoExploit / PoC in the wildCVE-2026-81934

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

Magento StyleSmuggler zero-day exploited to deploy Linux backdoor

StyleSmuggler zero-day in Magento and Adobe Commerce is actively exploited in the wild to deploy a Rust-based Linux backdoor; fix not yet released.

A zero-day dubbed StyleSmuggler affecting all versions of Magento and Adobe Commerce is being actively exploited, with the first observed incident on September 4 on a fully patched site. The exploit injects PHP code via Magento's template system through a fake 'failed-payment' email to achieve code execution, installing a Rust-based backdoor disguised as kworker/u:8:0 or fc-cache with a 30-minute cron job for persistence. The backdoor communicates via TLS/WebSockets or UDP port 123 masquerading as NTP traffic, checks TracerPid to detect tracing, and can receive remote commands. Adobe confirmed it is working on a fix with no timeline; Sansec recommends disabling GraphQL as mitigation and monitoring for suspicious cron entries and kworker or fc-cache processes. Magento is installed on more than 160,000 websites, including 14,000 of the top 1 million sites.

BleepingComputer · 9d agoExploit / PoC in the wild

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

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

U.S. CISA adds Red Hat, Linux Kernel, Ajax.NET Professional, Microsoft SQL Server, and Citrix NetScaler flaws to its Known Exploited Vulnerabilities catalog

CISA added six flaws, including actively exploited CVE-2026-8452 in Citrix NetScaler, to its Known Exploited Vulnerabilities catalog with federal patch deadlines.

CISA added six vulnerabilities to its KEV catalog: CVE-2015-3246 and CVE-2015-5287 (Red Hat libuser race condition and ABRT privilege escalation), CVE-2019-1068 (Microsoft SQL Server RCE), CVE-2021-23758 (Ajax.NET Professional deserialization), CVE-2022-0995 (Linux Kernel out-of-bounds write) and CVE-2026-8452 (Citrix NetScaler ADC/Gateway memory buffer flaw). CVE-2026-8452 has been observed under active exploitation in the wild and can cause denial-of-service. Under BOD 22-01, federal civilian agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.

Security Affairs · 19d agoExploit / PoC in the wildCVE-2015-3246CVE-2015-5287CVE-2019-1068+3 CVEs

August 2026 CVE Landscape

Insikt Group catalogs 73 high-impact August 2026 CVEs (43 Very Critical), including PaperCut, Zimbra, and Metabase flaws actively exploited or weaponized.

Recorded Future's Insikt Group identified 73 high-impact vulnerabilities in August 2026, 43 rated Very Critical, spanning 45 vendors with Microsoft accounting for roughly 11%. 31 vulnerabilities surfaced via CISA's KEV catalog, with others validated via open sources, vendor telemetry, and honeypot data. New Nuclei detection templates were released for CVE-2025-62593 (Ray), CVE-2026-72898 (Metabase), and CVE-2026-9198 (IBM Langflow). The report also highlights two AI-assisted operations: UAT-10147 exploited Zimbra, AjaxPro, Nacos, and Telerik servers before using DeepAudit and PentestGPT post-compromise, while a separate Chinese-speaking actor weaponized Hermes Agent and DeepSeek in a failed attempt.

Recorded Future · 8d agoVulnerability in the wildCVE-2025-62593CVE-2026-72898CVE-2026-9198+4 CVEs1

CISA Warns of Six Exploited Flaws in Microsoft, Linux, Red Hat and Citrix Products

CISA added six actively exploited vulnerabilities in Microsoft, Linux, Red Hat and Citrix products to its KEV catalog on August 26.

CISA added six new vulnerabilities to its Known Exploited Vulnerabilities catalog on August 26, citing signs of active exploitation in the wild. The affected products span Microsoft, Linux, Red Hat, and Citrix. Specific CVE identifiers and affected versions were not listed in the source text, but KEV listing requires confirmed exploitation.

Infosecurity Magazine · 20d agoExploit / PoC in the wild

CISA Adds Six Exploited Flaws to KEV, Including NetScaler, Linux, and SQL Server Bugs

CISA added six actively exploited flaws to KEV, led by Citrix NetScaler CVE-2026-8452, with federal patch deadlines set.

CISA added six flaws to the KEV catalog on August 27, 2026, citing evidence of active exploitation, led by CVE-2026-8452, an improper buffer restriction in Citrix NetScaler ADC and Gateway that can cause denial-of-service. Defused Cyber and Previdian reported active exploitation of CVE-2026-8452, with 36 attempts over 12 days from 12 attacker IPs deploying web shells x.php and z.php. The other additions cover SQL Server RCE (CVE-2019-1068), Linux kernel out-of-bounds write (CVE-2022-0995), Red Hat ABRT and libuser privilege escalations (CVE-2015-5287, CVE-2015-3246), and AjaxPro deserialization RCE (CVE-2021-23758). FCEB agencies must patch CVE-2019-1068 and CVE-2026-8452 by August 29, 2026, and the rest by September 9, 2026.

The Hacker News · 20d agoExploit / PoC in the wildCVE-2019-1068CVE-2026-8452CVE-2022-0995+3 CVEs

Nearly 800 Malicious npm Packages Deliver Cross

Nearly 800 typo-squatted npm packages deliver WEL1DROPPER, a cross-platform downloader installing RAT and infostealer payloads on Windows, macOS, Linux.

Researchers found roughly 800 npm packages with AI-generated typo-squat names that trigger a WEL1DROPPER downloader when loaded via require() rather than install hooks. The downloader fetches payloads from Cloudflare Workers hosts, falling back to DNS TXT records from wel1.ru, then achieves persistence, sandbox checks, ETW/AMSI patching and Sliver C2 deployment on Linux. Domains like tcsbank.ru suggest targeting of Russian financial institutions; Sonatype tracks the campaign as Flooding Dropper, a possible evolution of the Moika dependency-confusion campaign. Unit 42 separately documented npm/PyPI crypto stealers and malicious Chrome extensions that turn browsers into residential proxy crawlers.

The Hacker News · Aug 11, 2026Malware in the wild