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Hackers Actively Exploit Critical WooCommerce Plugin Vulnerability to Upload PHP Backdoors

Attackers actively exploit CVE-2026-27540 (CVSS 9.8) in WooCommerce Wholesale Lead Capture plugin to upload PHP webshells; patch shipped in version 2.0.3.2.

CVE-2026-27540 (CVSS 9.8) in the WooCommerce Wholesale Lead Capture plugin affects versions 2.0.3.1 and earlier across roughly 6,000 active installations. The unauthenticated AJAX handler wwlc_file_upload_handler trusts a client-supplied file_settings allowlist, letting attackers upload shell.php for remote code execution. Wordfence has blocked more than 100,000 exploit attempts since disclosure, with spikes in June, July, and August 2026. The vendor fixed the flaw in version 2.0.3.2.

GBHackersupdated · 3h agofirst · 20h agoExploit / PoC in the wild 4 sourcesCVE-2026-27540

Threat Brief: OWASSRF Vulnerability Exploitation

Unit 42 details active exploitation of Exchange SSRF flaws CVE-2022-41080/CVE-2022-41082 via the OWASSRF method, deploying the SilverArrow PowerShell backdoor.

Unit 42 documents OWASSRF, an exploit chain combining CVE-2022-41080 and CVE-2022-41082 to achieve remote code execution on Microsoft Exchange via Outlook Web Access, bypassing Microsoft's ProxyNotShell mitigations. Active exploitation was observed in late November and early December 2022, affecting at least eight organizations. Attackers authenticated to Exchange, then executed a PowerShell backdoor tracked as SilverArrow to create admin accounts, install AnyDesk, tunnel RDP via PuTTY Link, and dump LSASS memory for credential theft. Exploitation is isolated rather than mass-scale because authentication is required.

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

Chinese Hackers Use AI Agents in Multi

China-linked campaign used the SecFlow AI-agent framework (Claude, Qwen, DeepSeek) to automate intrusions against government targets in Taiwan, Indonesia, China and Vietnam.

Hunt.io documented a second China-linked campaign wiring commercial AI models into live cyberespionage, reconstructing the SecFlow orchestration system from five accidentally exposed open directories. Targets included Taiwan's Kuomintang Party archives, Indonesia's Ministry of Foreign Affairs, mainland Chinese government and education systems, and Vietnamese industrial hosts. The most extensive compromise hit a Fengtai District government Office Automation environment, yielding LSASS and registry hive theft, 822 user records and 1.28GB of attachments including patient health data. Tooling included a GLUTTON webshell hiding payloads in PNG pixels via steganography and a fake MySQL deserialization service for client-side code execution.

Security Affairs · 11d agoThreat actor in the wild