CVSS: 8.8EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29481 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29481
15 Dec 2020 — An issue was discovered in Xen through 4.14.x. Access rights of Xenstore nodes are per domid. Unfortunately, existing granted access rights are not removed when a domain is being destroyed. This means that a new domain created with the same domid will inherit the access rights to Xenstore nodes from the previous domain(s) with the same domid. Because all Xenstore entries of a guest below /local/domain/
CVSS: 6.0EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29484 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29484
15 Dec 2020 — An issue was discovered in Xen through 4.14.x. When a Xenstore watch fires, the xenstore client that registered the watch will receive a Xenstore message containing the path of the modified Xenstore entry that triggered the watch, and the tag that was specified when registering the watch. Any communication with xenstored is done via Xenstore messages, consisting of a message header and the payload. The payload length is limited to 4096 bytes. Any request to xenstored resulting in a response with a payload l... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-476: NULL Pointer Dereference •
CVSS: 6.5EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29483 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29483
15 Dec 2020 — An issue was discovered in Xen through 4.14.x. Xenstored and guests communicate via a shared memory page using a specific protocol. When a guest violates this protocol, xenstored will drop the connection to that guest. Unfortunately, this is done by just removing the guest from xenstored's internal management, resulting in the same actions as if the guest had been destroyed, including sending an @releaseDomain event. @releaseDomain events do not say that the guest has been removed. • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-416: Use After Free •
CVSS: 6.0EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29482 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29482
15 Dec 2020 — 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... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-426: Untrusted Search Path •
CVSS: 2.3EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29480 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29480
15 Dec 2020 — 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; nu... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-862: Missing Authorization •
CVSS: 8.8EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29479 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29479
15 Dec 2020 — 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 • CWE-862: Missing Authorization •
CVSS: 8.8EPSS: 0%CPEs: 15EXPL: 0CVE-2020-29569 – Debian Security Advisory 4843-1
https://notcve.org/view.php?id=CVE-2020-29569
15 Dec 2020 — 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 • CWE-416: Use After Free •
CVSS: 6.5EPSS: 0%CPEs: 3EXPL: 0CVE-2020-29568 – Debian Security Advisory 4843-1
https://notcve.org/view.php?id=CVE-2020-29568
15 Dec 2020 — 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 • CWE-770: Allocation of Resources Without Limits or Throttling •
CVSS: 6.2EPSS: 0%CPEs: 2EXPL: 0CVE-2020-29567 – Gentoo Linux Security Advisory 202107-30
https://notcve.org/view.php?id=CVE-2020-29567
15 Dec 2020 — An issue was discovered in Xen 4.14.x. When moving IRQs between CPUs to distribute the load of IRQ handling, IRQ vectors are dynamically allocated and de-allocated on the relevant CPUs. De-allocation has to happen when certain constraints are met. If these conditions are not met when first checked, the checking CPU may send an interrupt to itself, in the expectation that this IRQ will be delivered only after the condition preventing the cleanup has cleared. For two specific IRQ vectors, this expectation was... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OBLV6L6Q24PPQ2CRFXDX4Q76KU776GKI • CWE-770: Allocation of Resources Without Limits or Throttling •
CVSS: 5.5EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29566 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29566
15 Dec 2020 — An issue was discovered in Xen through 4.14.x. When they require assistance from the device model, x86 HVM guests must be temporarily de-scheduled. The device model will signal Xen when it has completed its operation, via an event channel, so that the relevant vCPU is rescheduled. If the device model were to signal Xen without having actually completed the operation, the de-schedule / re-schedule cycle would repeat. If, in addition, Xen is resignalled very quickly, the re-schedule may occur before the de-sc... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-674: Uncontrolled Recursion •