CVE-2020-29482
https://notcve.org/view.php?id=CVE-2020-29482
An issue was discovered in Xen through 4.14.x. A guest may access xenstore paths via absolute paths containing a full pathname, or via a relative path, which implicitly includes /local/domain/$DOMID for their own domain id. Management tools must access paths in guests' namespaces, necessarily using absolute paths. oxenstored imposes a pathname limit that is applied solely to the relative or absolute path specified by the client. Therefore, a guest can create paths in its own namespace which are too long for management tools to access. Depending on the toolstack in use, a malicious guest administrator might cause some management tools and debugging operations to fail. • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI https://www.debian.org/security/2020/dsa-4812 https://xenbits.xenproject.org/xsa/advisory-323.html • CWE-426: Untrusted Search Path •
CVE-2020-29480
https://notcve.org/view.php?id=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. • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI https://www.debian.org/security/2020/dsa-4812 https://xenbits.xenproject.org/xsa/advisory-115.html • CWE-862: Missing Authorization •
CVE-2020-29479
https://notcve.org/view.php?id=CVE-2020-29479
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.) • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI https://security.gentoo.org/glsa/202107-30 https://www.debian.org/security/2020/dsa-4812 https://xenbits.xenproject.org/xsa/advisory-353.html • CWE-862: Missing Authorization •
CVE-2020-29569
https://notcve.org/view.php?id=CVE-2020-29569
An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the states connect and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. • https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://security.gentoo.org/glsa/202107-30 https://security.netapp.com/advisory/ntap-20210205-0001 https://www.debian.org/security/2021/dsa-4843 https://xenbits.xenproject.org/xsa/advisory-350.html • CWE-416: Use After Free •
CVE-2020-29568
https://notcve.org/view.php?id=CVE-2020-29568
An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are processing watch events using a single thread. If the events are received faster than the thread is able to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable. • https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html https://security.gentoo.org/glsa/202107-30 https://www.debian.org/security/2021/dsa-4843 https://xenbits.xenproject.org/xsa/advisory-349.html • CWE-770: Allocation of Resources Without Limits or Throttling •