Cisco patches Secure Email Gateway zero-day exploited in attacks
Cisco patches actively exploited Secure Email Gateway zero-day CVE-2026-76461 enabling unauthenticated root command execution; CISA adds it to KEV.
Cisco disclosed that a critical zero-day (CVE-2026-76461) in the email parsing logic of AsyncOS for Secure Email Gateway is being actively exploited, allowing unauthenticated remote attackers to execute arbitrary SQL statements that lead to root-level command execution on virtual and physical appliances. CISA added the flaw to its KEV catalog and ordered federal agencies to patch within three days, by September 17. Cisco also patched four other critical SEG/SEWM vulnerabilities (CVE-2026-76440, CVE-2026-76441, CVE-2026-20353, CVE-2026-76443) with no evidence of exploitation, and shared IOCs including suspicious SQL statements in mail_logs.
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.
Attackers Exploit Critical Cisco FMC Flaw to deploy Qilin ransomware
Three threat groups, including Qilin ransomware operators, exploit critical Cisco FMC flaws CVE-2026-20079 and CVE-2026-20316 for root access, credential theft, and ransomware.
Cisco Talos identified three post-compromise clusters exploiting recently patched Cisco Secure Firewall Management Center flaws. UAT-12197 deploys JSP web shells and harvests credentials; UAT-11823 (with Sandworm-overlapping tooling) installs Cyclops Blink for persistence; UAT-11988 (Qilin) uses static credentials, extensive reconnaissance, SOCKS5 proxies, reverse-SSH tunnels, AV killers, and ransomware deployment. CISA added CVE-2026-20079 to the KEV catalog with a September 12, 2026 patch deadline for federal agencies; Cisco urges immediate hotfix application.
Unpatched Magento and Adobe Commerce Zero-Day Exploited to Backdoor Online Stores
Sansec reports active exploitation of an unpatched zero-day, dubbed StyleSmuggler, in Magento and Adobe Commerce, letting attackers backdoor online store servers without authentication.
Sansec disclosed on September 5 that attackers are exploiting an unpatched vulnerability, named StyleSmuggler, in Magento Open Source and Adobe Commerce to achieve unauthenticated remote code execution, with attacks observed starting September 4. All current versions including 2.4.9 are affected, and Adobe has published no advisory, CVE, patch, or workaround, with the next scheduled security release on September 8. Hosting firm Disrex Group independently confirmed two compromised stores (running 2.4.8 and 2.4.7-p2), both breached within the roughly eight-hour window before Sansec's blocking rules went live. The implant is a ~1.9 MB statically linked Rust binary disguised as a Linux kworker process, re-adding a cron entry every five minutes and in one case reading Magento sessions directly from Redis with no outbound traffic.
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.
Attackers exploit patched macOS Screen Sharing flaw to deploy cryptominer
Attackers actively exploit patched macOS Screen Sharing bug CVE-2026-65400 on systems with port 5900 exposed, gaining root to install a Monero cryptominer.
The Netherlands' National Cyber Security Centre (NCSC) reports active exploitation of CVE-2026-65400, an authentication flaw in macOS Screen Sharing that lets attackers authenticate without valid login credentials. Apple patched the issue in macOS Sequoia 15.7.9, Sonoma 14.8.9 and Tahoe 26.6.1, and the NCSC escalated its advisory on August 12 after proof-of-concept code went public and reports arrived of attacks on internet-exposed systems. In every reported case attackers obtained root access and installed a Monero crypto miner; users who cannot patch immediately are advised to disable Screen Sharing.
2026-002: Multiple Vulnerabilities in Cisco Products
Cisco fixed SD-WAN Controller auth bypass CVE-2026-20127 (CVSS 10) exploited in the wild since 2023, plus several critical and high flaws in SD-WAN Manager.
On 25 February 2026 Cisco released advisories for multiple flaws in Catalyst SD-WAN Controller and SD-WAN Manager, potentially granting administrative access to attackers. CVE-2026-20127 (CVSS 10.0) is an authentication bypass in the Controller's peering authentication mechanism, exploited in the wild since 2023, allowing unauthenticated admin access via NETCONF, rogue device injection, and persistent access. SD-WAN Manager flaws include CVE-2026-20129 (9.8, unauthenticated API auth bypass to netadmin), CVE-2026-20126 (7.8, local privesc to root), CVE-2026-20133 (7.5, info disclosure), CVE-2026-20122 (7.1, arbitrary file overwrite), and CVE-2026-20128 (5.5, DCA info disclosure). CERT-EU recommends patching, capturing forensic evidence, IOC hunting, and restricting management-plane internet exposure.