An issue was discovered in Xen through 4.14.x. In the Ocaml xenstored implementation, the internal representation of the tree has special cases for the root node, because this node has no parent. Unfortunately, permissions were not checked for certain operations on the root node. Unprivileged guests can get and modify permissions, list, and delete the root node. (Deleting the whole xenstore tree is a host-wide denial of service.) Achieving xenstore write access is also possible. All systems using oxenstored are vulnerable. Building and using oxenstored is the default in the upstream Xen distribution, if the Ocaml compiler is available. Systems using C xenstored are not vulnerable.
CWE-862
CVE-2020-29480
An issue was discovered in Xen through 4.14.x. Neither xenstore implementation does any permission checks when reporting a xenstore watch event. A guest administrator can watch the root xenstored node, which will cause notifications for every created, modified, and deleted key. A guest administrator can also use the special watches, which will cause a notification every time a domain is created and destroyed. Data may include: number, type, and domids of other VMs; existence and domids of driver domains; numbers of virtual interfaces, block devices, vcpus; existence of virtual framebuffers and their backend style (e.g., existence of VNC service); Xen VM UUIDs for other domains; timing information about domain creation and device setup; and some hints at the backend provisioning of VMs and their devices. The watch events do not contain values stored in xenstore, only key names. A guest administrator can observe non-sensitive domain and device lifecycle events relating to other guests. This information allows some insight into overall system configuration (including the number and general nature of other guests), and configuration of other guests (including the number and general nature of other guests’ devices). This information might be commercially interesting or might make other attacks easier. There is not believed to be exposure of sensitive data. Specifically, there is no exposure of VNC passwords, port numbers, pathnames in host and guest filesystems, cryptographic keys, or within-guest data.
CVE-2020-29158
An issue was discovered in Zammad before 3.5.1. An Agent with Customer permissions in a Group can bypass intended access control on internal Articles via the Ticket detail view.
CVE-2020-29160
An issue was discovered in Zammad before 3.5.1. A REST API call allows an attacker to change Ticket Article data in a way that defeats auditing.
CVE-2020-29006
MISP before 2.4.135 lacks an ACL check, related to app/Controller/GalaxyElementsController.php and app/Model/GalaxyElement.php.
CVE-2020-28215
A CWE-862: Missing Authorization vulnerability exists in Easergy T300 (firmware 2.7 and older), that could cause a wide range of problems, including information exposures, denial of service, and arbitrary code execution when access control checks are not applied consistently.