Modern virtualized service infrastructures expose attack vectors that enable attacks of high severity, such as attacks targeting hypervisors. A malicious user of a guest VM (virtual machine) may execute an attack against the underlying hypervisor via hypercalls, which are software traps from a kernel of a fully or partially paravirtualized guest VM to the hypervisor. The exploitation of a vulnerability of a hypercall handler may have severe consequences such as altering hypervisor's memory, which may result in the execution of malicious code with hypervisor privilege. Despite the importance of vulnerabilities of hypercall handlers, there is not much publicly available information on them. This significantly hinders advances towards securing hypercall interfaces. In this work, the researchers provide in-depth technical information on publicly disclosed vulnerabilities of hypercall handlers. Our vulnerability analysis is based on reverse engineering the released patches fixing the considered vulnerabilities. For each analyzed vulnerability, they provide background information essential for understanding the vulnerability, and information on the vulnerable hypercall handler and the error causing the vulnerability. The researchers also show how the vulnerability can be triggered and discuss the state of the targeted hypervisor after the vulnerability has been triggered.
7d90e4303005df5faec215e49bc919db7d1f13c6388d0b7871bb45c646e2e92aGentoo Linux Security Advisory 201309-24 - Multiple vulnerabilities have been found in Xen, allowing attackers on a Xen Virtual Machine to execute arbitrary code, cause Denial of Service, or gain access to data on the host. Versions less than 4.2.2-r1 are affected.
42fbd346dc4e79100c814835fd5068ef0a6bd2ccc23977307e7f191f8be1cc22Debian Linux Security Advisory 2582-1 - Multiple denial of service vulnerabilities have been discovered in the xen hypervisor. One of the issues (CVE-2012-5513) could even lead to privilege escalation from guest to host.
b1312d0fb2c22ab833dd73443d88403b729149ad1657106606fb476a56d90894Red Hat Security Advisory 2012-1540-01 - These packages contain the Linux kernel. A race condition in the way asynchronous I/O and fallocate() interacted when using ext4 could allow a local, unprivileged user to obtain random data from a deleted file. A flaw in the way the Xen hypervisor implementation range checked guest provided addresses in the XENMEM_exchange hypercall could allow a malicious, para-virtualized guest administrator to crash the hypervisor or, potentially, escalate their privileges, allowing them to execute arbitrary code at the hypervisor level.
906829b1fdfb32f66974a1ab2f6683d5132fe8b3ba63296b4d8f44c8427f38d5
© 2022 Packet Storm. All rights reserved.
%7Cutmcsr%3D(direct)%7Cutmcmd%3D(none)){kind=small}
Follow us on Twitter
Follow us on Facebook
Subscribe to an RSS Feed