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Clop-Linked Windchill Web Shell Decrypts Credentials and Maps Engineering Data

ReliaQuest details a bespoke JSP web shell that Clop deploys on hacked PTC Windchill and FlexPLM servers after exploiting CVE-2026-12569.

ReliaQuest analyzed a custom Java web shell planted on vulnerable PTC Windchill and FlexPLM servers following exploitation of CVE-2026-12569 (CVSS 9.3). The implant decrypts Windchill keystore credentials including the LDAP manager password, enumerates the file vault for engineering data, and loads attacker-supplied Java classes in memory for post-exploitation. Commands let operators read and delete files, exfiltrate results, and deliver follow-on payloads such as ransomware. Ransom-ISAC, eCrime.ch and Defused previously attributed the campaign to the Clop data-theft extortion group.

The Hacker News · 27d agoThreat actor in the wildCVE-2026-12569

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

F5 BIG-IP APM Malware Injects a PHP Web Shell Into Memory, Evading Disk Scans

Sophos found F5 BIG-IP APM malware that injects a PHP web shell into Apache's memory, evading disk scans, linked to exploited CVE-2025-53521.

Sophos's September 7 analysis describes malware tied to F5's c05d5254 activity that hooks apr_dso_load, modifies the libphp PHP module in memory, and injects a PHP web shell when Apache loads apm_css.php3, full_wt.php3 or webtop_popup_css.php3, leaving on-disk files clean. A separate installer infects /usr/sbin/httpd and umount, runs before Apache starts, disables SELinux (per ESET's related PoisonedRefresh analysis), and opens a local socket at /run/bigtlog.pipe for shell access. The activity is linked to CVE-2025-53521 in BIG-IP APM, rated 9.8 CVSS 3.1, patched in October 2025, added to CISA KEV on March 27, 2026.

The Hacker News · 7d agoMalware in the wildCVE-2025-53521

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

Persistent Attempts at Cyberespionage Against Southeast Asian Government Target Have Links to Alloy Taurus

Alloy Taurus (GALLIUM) compromised Southeast Asian government networks from 2022 to 2023 using Exchange web shells and undocumented .NET backdoors Reshell and Zapoa.

Unit 42 tracked persistent multiwave intrusions at a Southeast Asian government starting in early 2022 and continuing through 2023, attributing the activity with moderate confidence to Alloy Taurus (aka GALLIUM), a Chinese state-aligned espionage group. Attackers exploited Exchange Server vulnerabilities to deploy web shells including China Chopper, then ran reconnaissance with Fscan and WebScan, created administrative accounts, and installed undocumented .NET backdoors named Reshell and Zapoa. They established resilience by installing SoftEther VPN, brute-forced Active Directory credentials with Kerbrute, and dumped credential stores with GoDumpLsass and LsassUnhooker. The campaign reflects long-term espionage tradecraft to maintain a foothold.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild1

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

Attackers Exploit Critical Switchvox Flaw to Deploy Reverse Shells Without Credentials

Attackers exploit unauthenticated SQL injection CVE-2026-9586 in Sangoma Switchvox to run PostgreSQL commands and deploy reverse shells.

Threat actors are exploiting CVE-2026-9586 (CVSS 9.3), an unauthenticated SQL injection in Sangoma Switchvox SMB Edition 8.3 (104997), since August 30, 2026, running arbitrary SQL as the PostgreSQL superuser and achieving remote code execution. The /pa endpoint concatenates the user-controlled PhoneIP value into PostgreSQL queries; attackers can extract database contents, escalate to Switchvox web administrator, exfiltrate the cookie signing key to forge authentication, and invoke reverse shells. Sangoma patched the flaw in Switchvox 8.4.0.2 on July 14, 2026, roughly 4,000 instances are internet-exposed (mostly in the US), and honeypot activity from IP 176.65.148.184 deploys reverse shells followed by Base64-encoded process enumeration.

The Hacker News · 14d agoExploit / PoC in the wildCVE-2026-9586

Attackers Exploit WooCommerce Wholesale Lead Capture Flaw to Plant PHP Web Shells

Attackers exploit CVE-2026-27540 in WooCommerce Wholesale Lead Capture to upload PHP web shells; Wordfence blocked 100,000+ attempts since June 2026.

Wordfence reports active exploitation of CVE-2026-27540 (CVSS 9.8), an unauthenticated arbitrary file upload in the wwlc_file_upload_handler AJAX action of the WooCommerce Wholesale Lead Capture plugin (versions through 2.0.3.1, 6,000+ installs), enabling remote code execution via uploaded PHP web shells. Over 100,000 exploit attempts were blocked since June 2026, including 99 in the last 24 hours, traced to ten listed IP addresses. Separately, two critical flaws (CVE-2026-78159 and CVE-2026-78006) in The Events Calendar, installed on 600,000+ sites, allow unauthenticated RCE and full site takeover via PHP object injection chains. StellarWP patched the affected plugin versions 6.17.3 and 6.17.4 in releases 6.17.3.1 and 6.17.4.1.

The Hacker Newsupdated · 3h agofirst · 9h agoExploit / PoC in the wild 5 sourcesCVE-2026-27540CVE-2026-78159CVE-2026-78006

Hackers Exploit FortiGate SSL-VPN Flaw to Breach Thai ISP and Deploy MeshCentral Backdoor

Threat actors exploited FortiOS SSL-VPN flaw CVE-2024-21762 to breach Thai ISP Triple T Broadband, gaining root-level persistence via MeshCentral agents.

Attackers exploited CVE-2024-21762, an out-of-bounds write enabling unauthenticated RCE in FortiOS SSL-VPN, against Triple T Broadband's FortiGate 60F at mail.3bb.co.th, launching a Node.js reverse shell via a ROP payload. Hunt.io uncovered the operation through an exposed staging directory at 92.63.180[.]133:8888 containing 298 files of exploits, credential-harvesting scripts, session cookies, and a device inventory. Post-compromise, the actors deployed MeshCentral agents (device group TH-3BB, C2 www.ayuthayatech.com) running as root, plus a hidden SUID backdoor at /usr/local/bin/.rc, and also targeted an internal Pentaho/Tomcat server with Ghostcat (CVE-2020-1938). A cleanup script removed logs, shell histories, and web shells while deliberately preserving the MeshCentral agent and SUID backdoor.

GBHackers · 1d agoExploit / PoC in the wild 3 sourcesCVE-2024-21762CVE-2020-1938

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 · 7d agoMalware in the wildCVE-2025-53521

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

TrueConf Server Flaws Exploited to Replace Client Installers with PhantomCore

Head Mare exploits TrueConf server flaws to install web shells and deliver PhantomCore and PhantomGraph backdoors at Russian organizations.

Kaspersky detected July 2026 attacks by the threat actor Head Mare exploiting a vulnerability chain (KLCERT-26-057 and KLCERT-26-058) in unpatched TrueConf videoconferencing servers. The chain enables arbitrary code execution with SYSTEM privileges, deployment of a web shell at locale.php, and replacement of client installers with versions delivering the PhantomCore backdoor and PhantomGraph, which uses Microsoft OneDrive as C2. Targets span Russian instrumentation, electronics, transport, energy, IT, and software firms. Patches shipped in TrueConf Server 5.3.9, 5.4.9, and 5.5.5 on June 18, 2026.

The Hacker News · 26d agoThreat actor in the wild1

Cisco FMC flaws exploited by ransomware gang, state-sponsored hackers

Cisco Talos confirms ransomware and state-sponsored groups exploited CVE-2026-20079 and CVE-2026-20316 in Secure Firewall Management Center, deploying Qilin ransomware and Cyclops Blink.

Cisco Talos identified three threat clusters (UAT-12197, UAT-11823, UAT-11988) exploiting CVE-2026-20079, a CVSS 10.0 authentication bypass, and CVE-2026-20316, a CVSS 5.3 static-credential flaw, in Cisco Secure Firewall Management Center. Qilin affiliates used static credentials for reconnaissance and deployed Qilin ransomware; a Sandworm-linked cluster deployed a Cyclops Blink backdoor via a malicious license.tmp file; a third cluster stole credentials through a JSP web shell. Cisco has released hotfixes and urges immediate installation, with broader patches expected next week.

BleepingComputerupdated · 2d agofirst · 5d agoExploit / PoC in the wild 13 sourcesCVE-2026-20079CVE-2026-20316

Suspected China-Nexus Actor Exploits VMware vCenter Flaw, Deploys Babuk

QUIRSO attributes exploitation of VMware vCenter CVE-2026-59310 to a suspected China-nexus actor that hit 361 IPs in 47 countries, deploying backdoors and Babuk.

German incident response firm QUIRSOS assessed with moderate confidence that a suspected China-nexus actor, likely operating in UTC+08:00 hours, exploited VMware vCenter flaw CVE-2026-59310 (CVSS 9.8 directory traversal) beginning five days after Broadcom's July 29 patch. The campaign compromised 361 unique victim IPs across 47 countries, most in Germany, the US, Turkey, Iran, and France. The actor abused cron jobs, a XOR-obfuscated 'linuxFile' WebSocket backdoor with systemd/cron persistence, a JSP web shell, SSH authorized-keys manipulation, and a reverse SSH tool, with one Babuk deployment reported. A separate vCenter 'vcenter_admin' account creation consistent with CVE-2026-59309 exploitation was also observed from August 1.

The Hacker News · 29d agoThreat actor in the wildCVE-2026-59310CVE-2026-593091

CISA Flags Exploited Cisco, Citrix, Fortinet Flaws, Sets Sept. 12 Federal Patch Deadline

CISA adds actively exploited Cisco, Citrix, and Fortinet edge-device flaws to KEV catalog, ordering federal agencies to patch by September 12, 2026.

CISA added CVE-2026-20079 (Cisco Secure Firewall Management Center authentication bypass, CVSS 10.0), CVE-2026-19490 (Citrix NetScaler ADC/Gateway authentication bypass, CVSS 9.3), and CVE-2025-25249 (FortiOS heap buffer overflow, CVSS 7.3) to the Known Exploited Vulnerabilities catalog with a September 12, 2026 deadline for FCEB agencies. Cisco confirmed active exploitation of CVE-2026-20079 in August 2026, while Previdian honeypots logged 56 NetScaler exploitation attempts since September 3. SOCRadar attributes Fortinet exploitation to a financially motivated Russian-speaking actor deploying the PivotC2 Node.js RAT, infecting 178 of over 3,000 targeted IP addresses, mostly in the US.

The Hacker Newsupdated · 5d agofirst · 6d agoExploit / PoC in the wild 5 sourcesCVE-2026-20079CVE-2026-19490CVE-2025-252491

Amasty patches dozens of Magento extensions, 2 critical

Amasty patched dozens of Magento/Adobe Commerce extensions, including two critical flaws allowing unauthenticated web shell upload and remote code execution.

Extension vendor Amasty released fixes for a large batch of Magento and Adobe Commerce modules, with critical unauthenticated file upload flaws in Advanced Product Reviews and Gift Card that allow attackers to plant web shells and take full control of stores. Dozens of additional high-, medium- and low-severity extensions were also patched. The vendor says the release affects almost every Magento and Adobe Commerce store. A related Order Attributes flaw was previously exploited heavily, with Sansec Shield blocking over 12,000 attempts against 25% of Magento stores in three days.

Sansec (Magento / e-commerce security) · 6d agoVulnerability

H1 2026 Malware Vulnerability Trends

Recorded Future's H1 2026 report finds 215 actively exploited CVEs, RAT dominance, NFC payment fraud, and AI-augmented but not autonomous tradecraft.

Recorded Future's Insikt Group identified 215 actively exploited CVEs in H1 2026, up 34% from 161 in H1 2025, with the most impactful flaws combining network reachability, no authentication, and code execution. AsyncRAT was the top malware family, with AsyncRAT, Cobalt Strike, XWorm, Stealc, and REMCOS remaining top-ten staples; Android NFC malware like NFCShare and NGate enabled payment card theft and ATM cash-outs. AI-enabled attacks remained additive to established tradecraft, concentrated in Levels 1-3 of Recorded Future's AIM3 maturity model, with AI-assisted vulnerability research (e.g., Claude Mythos fixing 271 Firefox bugs in Firefox 150) inflating NVD disclosure volumes 43% above the prior six-month average. The report urges defenders to prioritize remotely exploitable RCE flaws, behavioral detection, developer credential security, and third-party oversight.

Recorded Future · 13d agoThreat actor in the wild1

⚡ Weekly Recap: AI-Powered PLC Attacks, GitLab Attacks, Stripe Key Leaks and More

US agencies warn of AI-assisted attacks on exposed Siemens PLCs; the week also saw GitLab CVE-2026-19478 exploited and trojanized npm packages found.

The weekly recap leads with a US government warning that threat actors use AI-generated scripts and Censys/ZoomEye scanning to attack internet-exposed Siemens S7 PLCs in water, energy and manufacturing, calling it an active threat. Other stories include active exploitation of GitLab CVE-2026-19478 (CVSS 9.4, unauthenticated project rewriting), 14 trojanized npm packages delivering the RedC2 4.0 Linux backdoor, and the Zombie Card attack that revives expired Visa cards for contactless payment fraud. It also covers suspected Russian clusters UNC6293, UNC7005 and UNC5976 phishing campaigns, a faster Cloudflare Workers Spectre JWT leak, and a bespoke Cl0p JSP web shell deployed after exploiting PTC Windchill flaws.

The Hacker News · 19d agoThreat actor in the wildCVE-2026-194781

New Mirai Variant Targeting Network Security Devices

New Mirai botnet variant exploits nine vulnerabilities in SonicWall, D-Link, Netgear, and other devices, with attacks ongoing at publication.

Unit 42 observed attacks exploiting VisualDoor (SonicWall SSL-VPN), CVE-2020-25506 (D-Link DNS-320), CVE-2020-26919 (Netgear ProSAFE Plus), and other flaws, with infrastructure rotating across at least three IP addresses between February 16 and March 13, 2021. Payloads were updated hours after CVE-2021-27561 and CVE-2021-27562 (Yealink Device Management, unauthenticated root RCE) and later added CVE-2021-22502 (Micro Focus Operation Bridge Reporter) and CVE-2019-19356 (Netis WF2419). Successful exploitation invokes wget to fetch shell scripts that download Mirai binaries compiled for multiple architectures and brute-forcers, and attacks were still ongoing when reported.

Palo Alto Unit 42 · 28d agoExploit / PoC in the wildCVE-2020-25506CVE-2020-26919CVE-2019-19356+3 CVEs