Articles by KENNETH

USN-5071-1: Linux kernel vulnerabilities Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel allowed a guest VM to disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a guest VM could use this to read or write portions of the host’s physical memory. (CVE-2021-3656) Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host’s physical memory. (CVE-2021-3653) It was discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not ensure enough processing time was given to perform cleanups of large SEV VMs. A local attacker could use this to [ more… ]

USN-5070-1: Linux kernel vulnerabilities Maxim Levitsky and Paolo Bonzini discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel allowed a guest VM to disable restrictions on VMLOAD/VMSAVE in a nested guest. An attacker in a guest VM could use this to read or write portions of the host’s physical memory. (CVE-2021-3656) Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host’s physical memory. (CVE-2021-3653) It was discovered that the Linux kernel did not properly enforce certain types of entries in the Secure Boot Forbidden Signature Database (aka dbx) protection mechanism. An attacker could use this to bypass UEFI Secure Boot restrictions. [ more… ]

USN-5069-2: mod-auth-mellon vulnerability USN-5069-1 fixed a vulnerability in mod-auth-mellon. This update provides the corresponding updates for Ubuntu 21.04. Original advisory details: It was discovered that mod-auth-mellon incorrectly filtered certain URLs. A remote attacker could possibly use this issue to perform an open redirect attack. Source: USN-5069-2: mod-auth-mellon vulnerability