CVSS: 7.8EPSS: 0%CPEs: 5EXPL: 0CVE-2021-28701 – Gentoo Linux Security Advisory 202208-23
https://notcve.org/view.php?id=CVE-2021-28701
08 Sep 2021 — Another race in XENMAPSPACE_grant_table handling Guests are permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, are de-allocated when a guest switches (back) from v2 to v1. Freeing such pages requires that the hypervisor enforce that no parallel request can result in the addition of a mapping of such a page to a guest. That enforcement was missing, allowing guests to retain... • http://www.openwall.com/lists/oss-security/2021/09/08/2 • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •
CVSS: 7.8EPSS: 0%CPEs: 5EXPL: 0CVE-2021-28697 – Gentoo Linux Security Advisory 202208-23
https://notcve.org/view.php?id=CVE-2021-28697
27 Aug 2021 — grant table v2 status pages may remain accessible after de-allocation Guest get permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, get de-allocated when a guest switched (back) from v2 to v1. The freeing of such pages requires that the hypervisor know where in the guest these pages were mapped. The hypervisor tracks only one use within guest space, but racing requests from... • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VQCFAPBNGBBAOMJZG6QBREOG5IIDZID • CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') •
CVSS: 5.5EPSS: 0%CPEs: 5EXPL: 0CVE-2021-28698 – Gentoo Linux Security Advisory 202208-23
https://notcve.org/view.php?id=CVE-2021-28698
27 Aug 2021 — long running loops in grant table handling In order to properly monitor resource use, Xen maintains information on the grant mappings a domain may create to map grants offered by other domains. In the process of carrying out certain actions, Xen would iterate over all such entries, including ones which aren't in use anymore and some which may have been created but never used. If the number of entries for a given domain is large enough, this iterating of the entire table may tie up a CPU for too long, starvi... • http://www.openwall.com/lists/oss-security/2021/09/01/2 • CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop') •
CVSS: 7.1EPSS: 0%CPEs: 1EXPL: 0CVE-2021-28692 – Debian Security Advisory 4931-1
https://notcve.org/view.php?id=CVE-2021-28692
28 Jun 2021 — inappropriate x86 IOMMU timeout detection / handling IOMMUs process commands issued to them in parallel with the operation of the CPU(s) issuing such commands. In the current implementation in Xen, asynchronous notification of the completion of such commands is not used. Instead, the issuing CPU spin-waits for the completion of the most recently issued command(s). Some of these waiting loops try to apply a timeout to fail overly-slow commands. The course of action upon a perceived timeout actually being det... • https://security.gentoo.org/glsa/202107-30 • CWE-269: Improper Privilege Management •
CVSS: 5.5EPSS: 0%CPEs: 1EXPL: 0CVE-2021-28689
https://notcve.org/view.php?id=CVE-2021-28689
11 Jun 2021 — x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware ... • https://xenbits.xenproject.org/xsa/advisory-370.txt • CWE-212: Improper Removal of Sensitive Information Before Storage or Transfer •
CVSS: 7.8EPSS: 0%CPEs: 2EXPL: 0CVE-2021-27379 – Debian Security Advisory 4888-1
https://notcve.org/view.php?id=CVE-2021-27379
18 Feb 2021 — An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access, and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush, and thus IOMMU updates were not always correct. NOTE: this issue exists because of an incomplete fix for CVE-2020-15565. Se detectó un problema en Xen versiones hasta 4.11.x, permitiendo a usuarios del Sistema Operativo invitado x86 Intel HVM obtener acceso DM... • http://www.openwall.com/lists/oss-security/2021/02/23/1 •
CVSS: 6.0EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29486 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29486
15 Dec 2020 — An issue was discovered in Xen through 4.14.x. Nodes in xenstore have an ownership. In oxenstored, a owner could give a node away. However, node ownership has quota implications. Any guest can run another guest out of quota, or create an unbounded number of nodes owned by dom0, thus running xenstored out of memory A malicious guest administrator can cause a denial of service against a specific guest or against the whole host. • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-770: Allocation of Resources Without Limits or Throttling •
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: 5.5EPSS: 0%CPEs: 4EXPL: 0CVE-2020-29485 – Debian Security Advisory 4812-1
https://notcve.org/view.php?id=CVE-2020-29485
15 Dec 2020 — An issue was discovered in Xen 4.6 through 4.14.x. When acting upon a guest XS_RESET_WATCHES request, not all tracking information is freed. A guest can cause unbounded memory usage in oxenstored. This can lead to a system-wide DoS. Only systems using the Ocaml Xenstored implementation are vulnerable. • https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2C6M6S3CIMEBACH6O7V4H2VDANMO6TVA • CWE-401: Missing Release of Memory after Effective Lifetime •
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 •