CVE-2020-15565
published 2020-07-07CVE-2020-15565: An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because…
PriorityP344high8.8CVSS 3.1
AVLACLPRLUINSCCHIHAH
EPSS
0.37%
28.9th percentile
An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ruled out. Xen versions from at least 3.2 onwards are affected. Only x86 Intel systems are affected. x86 AMD as well as Arm systems are not affected. Only x86 HVM guests using hardware assisted paging (HAP), having a passed through PCI device assigned, and having page table sharing enabled can leverage the vulnerability. Note that page table sharing will be enabled (by default) only if Xen considers IOMMU and CPU large page size support compatible.
Affected
18 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | xen | < xen 4.11.4+24-gddaaccbbab-1 (bookworm) | xen 4.11.4+24-gddaaccbbab-1 (bookworm) |
| debian | xen | < xen 4.14.0+80-gd101b417b7-1 (bookworm) | xen 4.14.0+80-gd101b417b7-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| opensuse | leap | — | — |
| opensuse | leap | — | — |
| xen | xen | >= 0 < 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.11.3+24-g14b62ab3e5-1ubuntu2.3 | 4.11.3+24-g14b62ab3e5-1ubuntu2.3 |
| xen | xen | >= 3.2.0 < 4.12.0 | 4.12.0 |
| xen | xen | 3.2.0 – 4.13.1 | — |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.06.1MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:C
osv8.8HIGH
vendor_debian8.8HIGH
vendor_redhat8.8HIGH
vendor_ubuntu5.5MEDIUM
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Ubuntu
Xen vulnerabilities
vendor_ubuntu·2022-09-19·CVSS 5.5
CVE-2020-25599 [MEDIUM] Xen vulnerabilities
Title: Xen vulnerabilities
Summary: Several security issues were fixed in Xen.
It was discovered that memory contents previously stored in
microarchitectural special registers after RDRAND, RDSEED, and SGX EGETKEY
read operations on Intel client and Xeon E3 processors may be briefly
exposed to processes on the same or different processor cores. A local
attacker could use this to expose sensitive information. (CVE-2020-0543)
Julien Grall discovered that Xen incorrectly handled memory barriers on
ARM-based systems. An attacker could possibly use this issue to cause a
denial of service, obtain sensitive information or escalate privileges.
(CVE-2020-11739)
Ilja Van Sprundel discovered that Xen incorrectly handled profiling of
guests. An unprivileged attacker could use this issue to obtain
Debian
CVE-2021-27379: xen - An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS u...
vendor_debian·2021·CVSS 8.8
CVE-2021-27379 [HIGH] CVE-2021-27379: xen - An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS u...
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.
Scope: local
bookworm: resolved (fixed in 4.14.0+80-gd101b417b7-1)
bullseye: resolved (fixed in 4.14.0+80-gd101b417b7-1)
forky: resolved (fixed in 4.14.0+80-gd101b417b7-1)
sid: resolved (fixed in 4.14.0+80-gd101b417b7-1)
trixie: resolved (fixed in 4.14.0+80-gd101b417b7-1)
Red Hat
xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
vendor_redhat·2020-07-07·CVSS 8.8
CVE-2020-15565 [HIGH] CWE-200 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes
Debian
CVE-2020-15565: xen - An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS u...
vendor_debian·2020·CVSS 8.8
CVE-2020-15565 [HIGH] CVE-2020-15565: xen - An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS u...
An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ru
OSV
xen vulnerabilities
osv·2022-09-19·CVSS 5.5
CVE-2020-0543 [MEDIUM] xen vulnerabilities
xen vulnerabilities
It was discovered that memory contents previously stored in
microarchitectural special registers after RDRAND, RDSEED, and SGX EGETKEY
read operations on Intel client and Xeon E3 processors may be briefly
exposed to processes on the same or different processor cores. A local
attacker could use this to expose sensitive information. (CVE-2020-0543)
Julien Grall discovered that Xen incorrectly handled memory barriers on
ARM-based systems. An attacker could possibly use this issue to cause a
denial of service, obtain sensitive information or escalate privileges.
(CVE-2020-11739)
Ilja Van Sprundel discovered that Xen incorrectly handled profiling of
guests. An unprivileged attacker could use this issue to obtain sensitive
information from other guests, cause a denial of s
GHSA
GHSA-f444-f4gw-jhg6: An issue was discovered in Xen through 4
ghsa_unreviewed·2022-05-24·CVSS 8.8
CVE-2021-27379 [HIGH] CWE-269 GHSA-f444-f4gw-jhg6: An issue was discovered in Xen through 4
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.
GHSA
GHSA-xcjp-mj7m-5f57: An issue was discovered in Xen through 4
ghsa_unreviewed·2022-05-24
CVE-2020-15565 [MEDIUM] CWE-400 GHSA-xcjp-mj7m-5f57: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ru
OSV
CVE-2021-27379: An issue was discovered in Xen through 4
osv·2021-02-18·CVSS 8.8
CVE-2021-27379 [HIGH] CVE-2021-27379: An issue was discovered in Xen through 4
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.
OSV
CVE-2020-15565: An issue was discovered in Xen through 4
osv·2020-07-07·CVSS 8.8
CVE-2020-15565 [HIGH] CVE-2020-15565: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.13.x, allowing x86 Intel HVM guest OS users to cause a host OS denial of service or possibly gain privileges because of insufficient cache write-back under VT-d. When page tables are shared between IOMMU and CPU, changes to them require flushing of both TLBs. Furthermore, IOMMUs may be non-coherent, and hence prior to flushing IOMMU TLBs, a CPU cache also needs writing back to memory after changes were made. Such writing back of cached data was missing in particular when splitting large page mappings into smaller granularity ones. A malicious guest may be able to retain read/write DMA access to frames returned to Xen's free pool, and later reused for another purpose. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ru
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321) [fedora-all]
bugzilla·2020-07-07·CVSS 8.8
CVE-2020-15565 [HIGH] CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321) [fedora-all]
CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321) [fedora-all]
This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected versions
of fedora-all.
For comments that are specific to the vulnerability please use bugs filed
against the "Security Response" product referenced in the "Blocks" field.
For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs
When submitting as an update, use the fedpkg template provided in the next
comment(s). This will include the bug IDs of this tracking bug as well as
the relevant top-level CVE bugs.
Please also mention the CVE IDs being fixed in the RPM changelog and the
fedpkg commit message.
NOTE: this issue affects multiple
Bugzilla
CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
bugzilla·2020-06-26·CVSS 8.8
CVE-2020-15565 [HIGH] CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
CVE-2020-15565 xen: insufficient cache write-back under VT-d leads to DoS (XSA-321)
A vulnerability was found in xe, where a malicious guest may be able to access sensitive information pertaining to other guests. Host crashes (leading to a Denial of Service) and privilege escalation cannot be ruled out.
Discussion:
Acknowledgments:
Name: the Xen project
---
Statement:
Only x86 HVM guests using hardware assisted paging (HAP), having a passed through PCI device assigned, and having page table sharing enabled can leverage the vulnerability. Note that page table sharing is enabled (by default) only if Xen considers IOMMU and CPU large page size support compatible. x86 AMD as well as ARM systems are not affected by this flaw.
---
Mitigation:
- Suppress the use of page table sharing (c
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00024.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00031.htmlhttp://www.openwall.com/lists/oss-security/2020/07/07/4http://xenbits.xen.org/xsa/advisory-321.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP/https://security.gentoo.org/glsa/202007-02https://www.debian.org/security/2020/dsa-4723http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00024.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-07/msg00031.htmlhttp://www.openwall.com/lists/oss-security/2020/07/07/4http://xenbits.xen.org/xsa/advisory-321.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP/https://security.gentoo.org/glsa/202007-02https://www.debian.org/security/2020/dsa-4723
2020-07-07
Published