CVE-2020-25603
published 2020-09-23CVE-2020-25603: An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures…
PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.41%
33.7th percentile
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to build Xen. We have not been able to survey compilers; consequently we cannot say which compiler(s) might produce vulnerable code (with which code generation options). GCC documentation clearly suggests that re-ordering is possible. Arm systems will also be vulnerable if the CPU is able to re-order memory access. Please consult your CPU vendor. x86 systems are only vulnerable if a compiler performs re-ordering.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | xen | < xen 4.14.0+80-gd101b417b7-1 (bookworm) | xen 4.14.0+80-gd101b417b7-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| opensuse | leap | — | — |
| xen | xen | <= 4.14.0 | — |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| xen | xen | >= 0 < 4.14.0+80-gd101b417b7-1 | 4.14.0+80-gd101b417b7-1 |
| 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 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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
Red Hat
xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
vendor_redhat·2020-09-22·CVSS 7.8
CVE-2020-25603 [HIGH] CWE-667 xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vu
Debian
CVE-2020-25603: xen - An issue was discovered in Xen through 4.14.x. There are missing memory barriers...
vendor_debian·2020·CVSS 7.8
CVE-2020-25603 [HIGH] CVE-2020-25603: xen - An issue was discovered in Xen through 4.14.x. There are missing memory barriers...
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to bui
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-27c2-9cc9-22v7: An issue was discovered in Xen through 4
ghsa_unreviewed·2022-05-24
CVE-2020-25603 [HIGH] CWE-401 GHSA-27c2-9cc9-22v7: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to bui
OSV
CVE-2020-25603: An issue was discovered in Xen through 4
osv·2020-09-23·CVSS 7.8
CVE-2020-25603 [HIGH] CVE-2020-25603: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.14.x. There are missing memory barriers when accessing/allocating an event channel. Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such a sequence is missing an appropriate memory barrier (e.g., smp_*mb()) to prevent both the compiler and CPU from re-ordering access. A malicious guest may be able to cause a hypervisor crash resulting in a Denial of Service (DoS). Information leak and privilege escalation cannot be excluded. Systems running all versions of Xen are affected. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all systems, the presence and the scope of the vulnerability depend on the precise re-ordering performed by the compiler used to bui
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340) [fedora-all]
bugzilla·2020-09-22·CVSS 7.8
CVE-2020-25603 [HIGH] CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340) [fedora-all]
CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340) [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 aff
Bugzilla
CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
bugzilla·2020-09-09·CVSS 7.8
CVE-2020-25603 [HIGH] CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
CVE-2020-25603 xen: missing memory barriers when accessing/allocating an event channel (XSA-340)
Event channels control structures can be accessed lockless as long as the port is considered to be valid. Such sequence is missing appropriate memory barrier (e.g smp_*mb()) to prevent both the compiler and CPU to re-order access.
Discussion:
Acknowledgments:
Name: the Xen project
---
Mitigation:
There is no known mitigation for this flaw apart from applying the patch.
---
Statement:
Systems running all versions of Xen are affected by this flaw. Whether a system is vulnerable will depend on the CPU and compiler used to build Xen. For all the systems, the presence and the scope of the vulnerability depends on the precise re-ordering performed by the compiler used to build Xen. x86 syst
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00008.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4JRXMKEMQRQYWYEPHVBIWUEAVQ3LU4FN/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DA633Y3G5KX7MKRN4PFEGM3IVTJMBEOM/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RJZERRBJN6E6STDCHT4JHP4MI6TKBCJE/https://security.gentoo.org/glsa/202011-06https://www.debian.org/security/2020/dsa-4769https://xenbits.xen.org/xsa/advisory-340.htmlhttp://lists.opensuse.org/opensuse-security-announce/2020-10/msg00008.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4JRXMKEMQRQYWYEPHVBIWUEAVQ3LU4FN/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DA633Y3G5KX7MKRN4PFEGM3IVTJMBEOM/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RJZERRBJN6E6STDCHT4JHP4MI6TKBCJE/https://security.gentoo.org/glsa/202011-06https://www.debian.org/security/2020/dsa-4769https://xenbits.xen.org/xsa/advisory-340.html
2020-09-23
Published