CVE-2020-11739
published 2020-04-14CVE-2020-11739: An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory…
PriorityP337high7.8CVSS 3.1
AVLACHPRLUINSCCHIHAH
EPSS
0.29%
20.7th percentile
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-table ones), so a malicious guest could exploit the race. For instance, there is a small window where Xen can leak memory if XENMAPSPACE_grant_table is used concurrently. A malicious guest may be able to leak memory, or cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded.
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | xen | < xen 4.11.4-1 (bookworm) | xen 4.11.4-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| opensuse | leap | — | — |
| xen | xen | <= 4.13.0 | — |
| xen | xen | — | — |
| xen | xen | >= 0 < 4.11.4-1 | 4.11.4-1 |
| xen | xen | >= 0 < 4.11.4-1 | 4.11.4-1 |
| xen | xen | >= 0 < 4.11.4-1 | 4.11.4-1 |
| xen | xen | >= 0 < 4.11.4-1 | 4.11.4-1 |
| xen | xen | >= 0 < 4.11.3+24-g14b62ab3e5-1ubuntu2.3 | 4.11.3+24-g14b62ab3e5-1ubuntu2.3 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
nvdv2.06.9MEDIUMAV:L/AC:M/Au:N/C:C/I:C/A:C
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu5.5MEDIUM
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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-5wwp-3576-jfjc: An issue was discovered in Xen through 4
ghsa_unreviewed·2022-05-24
CVE-2020-11739 [MEDIUM] CWE-119 GHSA-5wwp-3576-jfjc: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-ta
OSV
CVE-2020-11739: An issue was discovered in Xen through 4
osv·2020-04-14·CVSS 7.8
CVE-2020-11739 [HIGH] CVE-2020-11739: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-ta
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
Red Hat
xen: missing memory barriers in read-write unlock paths (XSA-314)
vendor_redhat·2020-04-14·CVSS 7.8
CVE-2020-11739 [HIGH] xen: missing memory barriers in read-write unlock paths (XSA-314)
xen: missing memory barriers in read-write unlock paths (XSA-314)
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe any
Debian
CVE-2020-11739: xen - An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause ...
vendor_debian·2020·CVSS 7.8
CVE-2020-11739 [HIGH] CVE-2020-11739: xen - An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause ...
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service or possibly gain privileges because of missing memory barriers in read-write unlock paths. The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones. In other words, the unlock may be seen by another processor before all the memory accesses within the "critical" section. As a consequence, it may be possible to have a writer executing a critical section at the same time as readers or another writer. In other words, many of the assumptions (e.g., a variable cannot be modified after a check) in the critical sections are not safe anymore. The read-write locks are used in hypercalls (such as grant-ta
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314) [fedora-all]
bugzilla·2020-04-14·CVSS 7.8
CVE-2020-11739 [HIGH] CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314) [fedora-all]
CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314) [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 su
Bugzilla
CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314)
bugzilla·2020-04-14·CVSS 7.8
CVE-2020-11739 [HIGH] CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314)
CVE-2020-11739 xen: missing memory barriers in read-write unlock paths (XSA-314)
The read-write unlock paths don't contain a memory barrier. On Arm, this means a processor is allowed to re-order the memory access with the preceding ones.
Reference:
https://xenbits.xen.org/xsa/advisory-314.html
Discussion:
Created xen tracking bugs for this issue:
Affects: fedora-all [bug 1823784]
http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00006.htmlhttp://www.openwall.com/lists/oss-security/2020/04/14/2http://xenbits.xen.org/xsa/advisory-314.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5M2XRNCHOGGTJQBZQJ7DCV6ZNAKN3LE2/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NVTP4OYHCTRU3ONFJOFJQVNDFB25KLLG/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YMAW7D2MP6RE4BFI5BZWOBBWGY3VSOFN/https://security.gentoo.org/glsa/202005-08https://www.debian.org/security/2020/dsa-4723https://xenbits.xen.org/xsa/advisory-314.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-05/msg00006.htmlhttp://www.openwall.com/lists/oss-security/2020/04/14/2http://xenbits.xen.org/xsa/advisory-314.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5M2XRNCHOGGTJQBZQJ7DCV6ZNAKN3LE2/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NVTP4OYHCTRU3ONFJOFJQVNDFB25KLLG/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YMAW7D2MP6RE4BFI5BZWOBBWGY3VSOFN/https://security.gentoo.org/glsa/202005-08https://www.debian.org/security/2020/dsa-4723https://xenbits.xen.org/xsa/advisory-314.html
2020-04-14
Published