Virtualization Security | Breaking Cybersecurity News | The Hacker News

Security researcher Malcolm Stagg has disclosed a new attack class called  NatJack  that manipulates network address translation (NAT) connection state to hijack active TCP sessions, spoof DNS responses, expose mapped ports, and exhaust NAT tables. Presented at Black Hat USA 2026 , the research found affected behavior across independently developed implementations, including Windows and Linux. Two implementation-specific flaws have been assigned CVEs:  CVE-2026-56181  (CVSS score: 8.3) in Windows NAT used by Hyper-V, and  CVE-2026-63913  (CVSS score: 8.2) in Linux Netfilter conntrack. NatJack generally requires the attacker to have privileged access to a system behind the same NAT as the victim. The mitigation guidance therefore emphasizes separating untrusted workloads from trusted systems that share NAT infrastructure. There is no single patch for the broader attack class. Organizations should apply available Windows and Linux updates and encryp...

Zapscape , a new Linux kernel vulnerability, could allow an attacker with kernel privileges inside an L1 guest virtual machine (VM) to escape KVM isolation and execute code on the host. The risk applies when nested virtualization is exposed to untrusted guests. The flaw is tracked as  CVE-2026-64561  and affects KVM/x86's shadow memory management unit (MMU), which manages shadow page tables used for nested guest memory translation. Security researcher Hyunwoo Kim, who disclosed the bug, said the demonstrated exploit path can run commands on the host with kernel, or root, privileges. The upstream fix has been merged, and administrators running KVM hosts that expose nested virtualization to untrusted guests should update to a fixed stable kernel or a vendor package that backports the patch. The required L1 kernel privilege usually means guest root. Intel systems also require both EPT page-walk length 4 and 5 to be exposed to the L1 guest. AMD has no equivalent conditio...

Broadcom has released security updates to address multiple security flaws impacting VMware ESX, vCenter, Workstation, and Fusion, three of which have been designated as critical in severity. The first of the three critical-rated flaws is CVE-2026-59309 (CVSS score: 9.8), which has been described as an authentication bypass in VMware vCenter. "A malicious actor with network access to vCenter may exploit this issue to bypass authentication and gain unauthorized access to the system," Broadcom said. The second critical flaw is a directory-traversal vulnerability in vCenter ( CVE-2026-59310 , CVSS score: 9.8) that a malicious actor with network access can exploit to execute arbitrary code. Both vulnerabilities have been addressed in the versions below - VMware Cloud Foundation, VMware vSphere Foundation versions 9.1.x.x (Fixed in 9.1.0.0300) VMware Cloud Foundation, VMware vSphere Foundation versions 9.0.x.x (Fixed in 9.0.2.0100) VMware vCenter version...

Cybersecurity researchers have charted the evolution of INC from an nascent ransomware-as-a-service (RaaS) operation to one of the most prolific cybercrime groups in 2026, claiming no less than 830 victims since August 2023. "The disruption of LockBit and the shutdown of BlackCat created opportunities for INC to expand as affiliates migrated to alternative ransomware operations," Acronis researcher Darrel Virtusio said . "United States organizations account for more than 65% of listed victims, with legal services, manufacturing, construction, technology and health care among the most targeted sectors." INC's Windows and Linux/ESXi encryptors have also been rewritten in Rust to facilitate easier cross-platform development and better resist reverse engineering efforts. Attacks deploying the ransomware are characterized by the use of an updated credential dumper capable of targeting newer Veeam backup deployments that use the salted DPAPI credential encryp...