U.S. flag   An official website of the United States government
Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock (Dot gov) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results (Refine Search)

Search Parameters:
  • Keyword (text search): cpe:2.3:o:xen:xen:4.1.1:*:*:*:*:*:*:*
  • CPE Name Search: true
There are 233 matching records.
Displaying matches 1 through 20.
Vuln ID Summary CVSS Severity
CVE-2022-42324

Oxenstored 32->31 bit integer truncation issues Integers in Ocaml are 63 or 31 bits of signed precision. The Ocaml Xenbus library takes a C uint32_t out of the ring and casts it directly to an Ocaml integer. In 64-bit Ocaml builds this is fine, but in 32-bit builds, it truncates off the most significant bit, and then creates unsigned/signed confusion in the remainder. This in turn can feed a negative value into logic not expecting a negative value, resulting in unexpected exceptions being thrown. The unexpected exception is not handled suitably, creating a busy-loop trying (and failing) to take the bad packet out of the xenstore ring.

Published: November 01, 2022; 9:15:12 AM -0400
V3.1: 5.5 MEDIUM
V2.0:(not available)
CVE-2022-33748

lock order inversion in transitive grant copy handling As part of XSA-226 a missing cleanup call was inserted on an error handling path. While doing so, locking requirements were not paid attention to. As a result two cooperating guests granting each other transitive grants can cause locks to be acquired nested within one another, but in respectively opposite order. With suitable timing between the involved grant copy operations this may result in the locking up of a CPU.

Published: October 11, 2022; 9:15:10 AM -0400
V3.1: 5.6 MEDIUM
V2.0:(not available)
CVE-2022-33747

Arm: unbounded memory consumption for 2nd-level page tables Certain actions require e.g. removing pages from a guest's P2M (Physical-to-Machine) mapping. When large pages are in use to map guest pages in the 2nd-stage page tables, such a removal operation may incur a memory allocation (to replace a large mapping with individual smaller ones). These memory allocations are taken from the global memory pool. A malicious guest might be able to cause the global memory pool to be exhausted by manipulating its own P2M mappings.

Published: October 11, 2022; 9:15:10 AM -0400
V3.1: 3.8 LOW
V2.0:(not available)
CVE-2022-33745

insufficient TLB flush for x86 PV guests in shadow mode For migration as well as to work around kernels unaware of L1TF (see XSA-273), PV guests may be run in shadow paging mode. To address XSA-401, code was moved inside a function in Xen. This code movement missed a variable changing meaning / value between old and new code positions. The now wrong use of the variable did lead to a wrong TLB flush condition, omitting flushes where such are necessary.

Published: July 26, 2022; 9:15:10 AM -0400
V3.1: 8.8 HIGH
V2.0:(not available)
CVE-2022-21166

Incomplete cleanup in specific special register write operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Published: June 15, 2022; 5:15:09 PM -0400
V3.1: 5.5 MEDIUM
V2.0: 2.1 LOW
CVE-2022-21127

Incomplete cleanup in specific special register read operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Published: June 15, 2022; 4:15:17 PM -0400
V3.1: 5.5 MEDIUM
V2.0: 2.1 LOW
CVE-2022-21125

Incomplete cleanup of microarchitectural fill buffers on some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Published: June 15, 2022; 4:15:17 PM -0400
V3.1: 5.5 MEDIUM
V2.0: 2.1 LOW
CVE-2022-21123

Incomplete cleanup of multi-core shared buffers for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.

Published: June 15, 2022; 4:15:17 PM -0400
V3.1: 5.5 MEDIUM
V2.0: 2.1 LOW
CVE-2022-26364

x86 pv: Insufficient care with non-coherent mappings T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, Xen's safety logic doesn't account for CPU-induced cache non-coherency; cases where the CPU can cause the content of the cache to be different to the content in main memory. In such cases, Xen's safety logic can incorrectly conclude that the contents of a page is safe.

Published: June 09, 2022; 1:15:09 PM -0400
V3.1: 6.7 MEDIUM
V2.0: 7.2 HIGH
CVE-2022-26363

x86 pv: Insufficient care with non-coherent mappings T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, Xen's safety logic doesn't account for CPU-induced cache non-coherency; cases where the CPU can cause the content of the cache to be different to the content in main memory. In such cases, Xen's safety logic can incorrectly conclude that the contents of a page is safe.

Published: June 09, 2022; 1:15:08 PM -0400
V3.1: 6.7 MEDIUM
V2.0: 7.2 HIGH
CVE-2022-26362

x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited.

Published: June 09, 2022; 1:15:08 PM -0400
V3.1: 6.4 MEDIUM
V2.0: 6.9 MEDIUM
CVE-2022-26356

Racy interactions between dirty vram tracking and paging log dirty hypercalls Activation of log dirty mode done by XEN_DMOP_track_dirty_vram (was named HVMOP_track_dirty_vram before Xen 4.9) is racy with ongoing log dirty hypercalls. A suitably timed call to XEN_DMOP_track_dirty_vram can enable log dirty while another CPU is still in the process of tearing down the structures related to a previously enabled log dirty mode (XEN_DOMCTL_SHADOW_OP_OFF). This is due to lack of mutually exclusive locking between both operations and can lead to entries being added in already freed slots, resulting in a memory leak.

Published: April 05, 2022; 9:15:07 AM -0400
V3.1: 5.6 MEDIUM
V2.0: 4.0 MEDIUM
CVE-2022-23034

A PV guest could DoS Xen while unmapping a grant To address XSA-380, reference counting was introduced for grant mappings for the case where a PV guest would have the IOMMU enabled. PV guests can request two forms of mappings. When both are in use for any individual mapping, unmapping of such a mapping can be requested in two steps. The reference count for such a mapping would then mistakenly be decremented twice. Underflow of the counters gets detected, resulting in the triggering of a hypervisor bug check.

Published: January 25, 2022; 9:15:09 AM -0500
V3.1: 5.5 MEDIUM
V2.0: 2.1 LOW
CVE-2021-28703

grant table v2 status pages may remain accessible after de-allocation (take two) 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 the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. Upon switching back from v2 to v1, the guest would then retain access to a page that was freed and perhaps re-used for other purposes. This bug was fortuitously fixed by code cleanup in Xen 4.14, and backported to security-supported Xen branches as a prerequisite of the fix for XSA-378.

Published: December 07, 2021; 7:15:08 AM -0500
V3.1: 7.0 HIGH
V2.0: 6.9 MEDIUM
CVE-2021-28709

issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assigned. Guests are permitted to control certain P2M aspects of individual pages via hypercalls. These hypercalls may act on ranges of pages specified via page orders (resulting in a power-of-2 number of pages). In some cases the hypervisor carries out the requests by splitting them into smaller chunks. Error handling in certain PoD cases has been insufficient in that in particular partial success of some operations was not properly accounted for. There are two code paths affected - page removal (CVE-2021-28705) and insertion of new pages (CVE-2021-28709). (We provide one patch which combines the fix to both issues.)

Published: November 23, 2021; 9:15:06 PM -0500
V3.1: 7.8 HIGH
V2.0: 6.9 MEDIUM
CVE-2021-28705

issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assigned. Guests are permitted to control certain P2M aspects of individual pages via hypercalls. These hypercalls may act on ranges of pages specified via page orders (resulting in a power-of-2 number of pages). In some cases the hypervisor carries out the requests by splitting them into smaller chunks. Error handling in certain PoD cases has been insufficient in that in particular partial success of some operations was not properly accounted for. There are two code paths affected - page removal (CVE-2021-28705) and insertion of new pages (CVE-2021-28709). (We provide one patch which combines the fix to both issues.)

Published: November 23, 2021; 9:15:06 PM -0500
V3.1: 7.8 HIGH
V2.0: 6.9 MEDIUM
CVE-2021-28706

guests may exceed their designated memory limit When a guest is permitted to have close to 16TiB of memory, it may be able to issue hypercalls to increase its memory allocation beyond the administrator established limit. This is a result of a calculation done with 32-bit precision, which may overflow. It would then only be the overflowed (and hence small) number which gets compared against the established upper bound.

Published: November 23, 2021; 8:15:08 PM -0500
V3.1: 8.6 HIGH
V2.0: 7.8 HIGH
CVE-2021-28701

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 access to pages that were freed and perhaps re-used for other purposes. Unfortunately, when XSA-379 was being prepared, this similar issue was not noticed.

Published: September 08, 2021; 10:15:08 AM -0400
V3.1: 7.8 HIGH
V2.0: 4.4 MEDIUM
CVE-2021-28698

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, starving other domains or causing issues in the hypervisor itself. Note that a domain may map its own grants, i.e. there is no need for multiple domains to be involved here. A pair of "cooperating" guests may, however, cause the effects to be more severe.

Published: August 27, 2021; 3:15:07 PM -0400
V3.1: 5.5 MEDIUM
V2.0: 4.9 MEDIUM
CVE-2021-28697

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 the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. Upon switching back from v2 to v1, the guest would then retain access to a page that was freed and perhaps re-used for other purposes.

Published: August 27, 2021; 3:15:07 PM -0400
V3.1: 7.8 HIGH
V2.0: 4.6 MEDIUM