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.
Microsoft’s September 2026 Patch Tuesday addresses 964 CVEs (CVE-2026-81963, CVE-2026-85880)
Microsoft's September 2026 Patch Tuesday fixes a record 964 CVEs, including two zero-days actively exploited in the wild.
Microsoft patched a record 964 CVEs in its September 2026 Patch Tuesday release, with 101 rated critical and 824 rated important, making it the largest Patch Tuesday to date. The release includes fixes for two zero-days that were exploited in the wild, with CVE-2026-81963 and CVE-2026-85880 highlighted in the release. Affected products span Windows core components, Office, Exchange, .NET, Visual Studio, Active Directory services (including AD CS and AD FS) and numerous Azure services. Tenable notes the release surpasses July's as the biggest ever.
Artifactory flaws chained in attacks deploying backdoor malware
Attackers chain JFrog Artifactory flaws CVE-2026-42018 and CVE-2026-42016 to gain admin tokens and deploy a Rust backdoor on self-hosted servers.
Wiz observed multiple threat actors chaining CVE-2026-42018 and CVE-2026-42016 against self-hosted JFrog Artifactory instances between August 15 and September 8, 2026, in some cases obtaining admin access in under five minutes. The critical authentication bypass CVE-2026-82329 was also exploited this month to mint administrator tokens. Attackers installed malicious Groovy plugins, dropped a Rust backdoor with C2 capabilities, uploaded webshells, stole configuration data and cluster join keys, and added SSH keys to new accounts. Wiz estimates 49-62% of internet-reachable Artifactory instances are vulnerable to at least one of the three flaws, and patched releases from 7.111.21 through 7.161.20 are available.
SAP September 2026 Security Update Fixes 4 Critical Vulnerabilities and 15 Other Flaws
SAP's September 2026 Patch Tuesday ships 19 security notes, including four criticals led by a CVSS 10.0 memory-corruption flaw in Extended Passport Processing.
SAP released 19 new Security Notes plus one update, fixing four critical vulnerabilities and 15 additional flaws. The most urgent is CVE-2026-44756 (CVSS 10.0), memory corruption in Extended Passport (EPP) Processing affecting many SAP Kernel and Web Dispatcher releases. Other criticals include CVE-2026-58240 (NetWeaver Message Server missing authentication, 9.8), CVE-2026-76969 (credential disclosure in CAP sap/cds-mtxs, 9.4), and CVE-2026-66768 (improper access control in SAP GUI for Java, 9.0). High-severity fixes cover XXE in Integration Suite Trading Partner Management, deserialization in NetWeaver Business Client, and memory corruption in NetWeaver AS for ABAP.
BigBear 2 PhaaS Campaign Steals 5000+ Microsoft Credentials
CloudSEK researchers found the BigBear 2.0 PhaaS kit, built on Evilginx2, has stolen over 5,100 Microsoft 365 credentials across 461 organizations in 40+ countries.
CloudSEK gained admin access to the BigBear 2.0 phishing-as-a-service panel, an Evilginx2-based adversary-in-the-middle platform operated by someone using the alias 'General Boss'. The team observed 3,331 unique victim IPs across more than 40 countries, 42 VPS nodes mostly on Vultr, and 5,137 credential records across 461 organizations, including 4,148 session cookies, 1,032 plaintext passwords, and 474 completed MFA-bypassed authentications. IT and managed service providers were the most targeted sector, raising supply-chain risk since their compromise can expose client infrastructure and privileged Azure AD access.
Attackers Exploit MLflow SSRF Flaw to Steal Cloud Credentials and Secrets
Attackers exploit MLflow SSRF CVE-2026-64849 (CVSS 9.3) to steal cloud credentials; CISA added it to KEV; FUXA flaw CVE-2026-25895 is being scanned.
watchTowr observed exploitation of MLflow CVE-2026-64849, an unauthenticated SSRF (CVSS 9.3) affecting versions below 3.15.0, within hours of CVE assignment on August 17, 2026, with attackers abusing model-registry webhooks to reach cloud metadata endpoints and exfiltrate credentials and secrets. CISA added the flaw to its Known Exploited Vulnerabilities catalog on August 19, 2026, with a September 2 patch deadline for federal civilian agencies. VulnCheck reported scanning of FUXA CVE-2026-25895 (missing authentication plus path traversal, CVSS 9.5, versions through 1.2.9) beginning August 18; about 60 FUXA instances are exposed and no RCE payloads have been dropped yet.
Medusa ransomware gang has hit over 500 organizations, CISA warns
FBI, CISA, and HHS warn Medusa ransomware has hit over 500 organizations across critical infrastructure since June 2021, using phishing and unpatched flaws.
An updated joint advisory from CISA, FBI, and HHS states Medusa ransomware has affected more than 500 organizations, spanning healthcare, defense, manufacturing, government, IT, financial services, education, insurance, and legal sectors. Since early 2023 Medusa has operated a ransomware-as-a-service affiliate model and buys access from initial access brokers for $100 to $1 million. Affiliates gain entry via phishing and unpatched internet-facing software, exploiting newly disclosed flaws in ScreenConnect, Fortinet EMS, Fortra GoAnywhere, and BeyondTrust within 24 hours. The group runs double extortion, giving victims 48 hours before leak-site publication, with $10,000 in cryptocurrency buying a one-day delay.
Critical Security Issue Affecting TeamCity On-Premises (CVE-2026-63077 ...
JetBrains fixed critical unauthenticated RCE CVE-2026-63077 in TeamCity On-Premises; update to 2025.11.7 or 2026.1.3.
JetBrains disclosed CVE-2026-63077, a critical unauthenticated remote code execution vulnerability affecting all TeamCity On-Premises versions. An attacker with HTTP(S) access can bypass authentication checks via the TeamCity agent polling protocol and execute arbitrary operating system commands with the privileges of the server process. Fixes are available in versions 2025.11.7 and 2026.1.3, plus a security patch plugin for TeamCity 2017.1+. JetBrains states there is no evidence of active exploitation at disclosure time, and TeamCity Cloud is already mitigated.
Chaotic Eclipse Released ShieldCrash, A PoC For Microsoft Defender Zero-Day
Researcher Chaotic Eclipse released ShieldCrash, a PoC showing Microsoft Defender's CVE-2026-69414 patch is incomplete, enabling arbitrary file reads as SYSTEM.
Security researcher Chaotic Eclipse published ShieldCrash, a proof-of-concept exploit for the Microsoft Malware Protection Engine privilege escalation vulnerability CVE-2026-69414 (ShieldBreak). The PoC performs arbitrary file reads with SYSTEM privileges on all supported Windows versions, including systems running the September 2026 security updates and Malware Protection Engine version 1.1.26080.3. The researcher claims Microsoft's patch fixed several exploit paths but missed a specific condition that still enables the attack. His recent releases also include zero-day PoCs targeting Nvidia, Kaspersky, Avast, and CrowdStrike Falcon.
SAP Patches CVSS 10.0 Kernel Flaw Enabling Unauthenticated Remote Code Execution
SAP patched CVE-2026-44756 (CVSS 10.0), an unauthenticated kernel memory corruption allowing OS command execution, plus three other critical flaws.
SAP's September security updates include CVE-2026-44756 (OVERPASS, CVSS 10.0), a missing boundary validation during deserialization of Extended Passport (EPP) data in the SAP kernel, enabling unauthenticated attackers to run arbitrary OS commands with SAP administrative privileges. Also patched: CVE-2026-58240 (S4GET, CVSS 9.8), a missing authentication check in SAP NetWeaver Message Server yielding RCE as <sid>adm; CVE-2026-76969 (9.4), credential disclosure in SAP Cloud Application Programming Model multi-tenant apps; and CVE-2026-66768 (9.0), improper access control in SAP NetWeaver SAP GUI for Java. Onapsis, which discovered the flaws, says none have been exploited to date and recommends prioritizing internet-facing SAP systems.
Critical Dell ObjectScale Vulnerabilities Allows Malicious Users to Compromise the Affected system
Dell's DSA-2026-393 fixes ObjectScale/ECS flaws including unauthenticated deserialization RCE CVE-2026-70416 rated CVSS 10.0.
Dell advisory DSA-2026-393 (September 10, 2026) covers multiple flaws in ObjectScale and Elastic Cloud Storage (ECS). CVE-2026-70416 is a critical untrusted-data deserialization RCE (CVSS 10.0) in ObjectScale before 4.4.0.0 allowing unauthenticated remote code execution and full environment takeover, credited to researcher WinD39 (Huynh Dinh Vu). Additional issues include CVE-2025-43936 improper authentication (8.1), CVE-2026-26947 privilege management (6.7), CVE-2026-36591-style weak crypto CVE-2025-36591 (4.4), CVE-2026-76104 permission assignment DoS (5.5), plus third-party CVEs in Apache Log4j, liblzma, and the Linux kernel. Dell advises upgrading to version 4.4.0.0 or later (or 4.2.0.1) and restricting management interfaces until patched.
AL26-019 - Vulnerabilities impacting Citrix NetScaler ADC and NetScaler Gateway - CVE-2026-19490 and CVE-2026-19489
Canadian Cyber Centre alerts on Citrix NetScaler ADC/Gateway flaws CVE-2026-19490 (authentication bypass) and CVE-2026-19489 (buffer overflow), urging emergency patching.
The Canadian Centre for Cyber Security issued alert AL26-019 covering two Citrix NetScaler vulnerabilities disclosed in a vendor advisory on August 19, 2026. CVE-2026-19490 (CWE-288) allows a remote unauthenticated attacker to bypass authentication on appliances configured as a Gateway for SSL VPN, ICA Proxy, CVPN, RDP Proxy, or as an AAA virtual server. CVE-2026-19489 (CWE-120) is a classic buffer overflow that may cause memory overflow, unpredictable behavior, or denial-of-service conditions. Affected appliances are vulnerable when configured as a SAML IdP; fixed versions include 14.1-73.32, 13.1-63.21, and 13.1-37.277 for FIPS.