CVE-2020-25600
published 2020-09-23CVE-2020-25600: An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model…
PriorityP421medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.43%
34.9th percentile
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in Xen, 32-bit domains (including Domain 0) servicing other domains may observe event channel allocations to succeed when they should really fail. Subsequent use of such event channels would then possibly lead to corruption of other parts of the shared info structure. An unprivileged guest may cause another domain, in particular Domain 0, to misbehave. This may lead to a Denial of Service (DoS) for the entire system. All Xen versions from 4.4 onwards are vulnerable. Xen versions 4.3 and earlier are not vulnerable. Only x86 32-bit domains servicing other domains are vulnerable. Arm systems, as well as x86 64-bit domains, are not vulnerable.
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 | >= 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 |
| xen | xen | 4.4.0 – 4.14.0 | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvdv2.04.9MEDIUMAV:L/AC:L/Au:N/C:N/I:N/A:C
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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: out of bounds event channels available to 32-bit x86 domains (XSA-342)
vendor_redhat·2020-09-22·CVSS 5.5
CVE-2020-25600 [MEDIUM] CWE-440 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342)
xen: out of bounds event channels available to 32-bit x86 domains (XSA-342)
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-b
Debian
CVE-2020-25600: xen - An issue was discovered in Xen through 4.14.x. Out of bounds event channels are ...
vendor_debian·2020·CVSS 5.5
CVE-2020-25600 [MEDIUM] CVE-2020-25600: xen - An issue was discovered in Xen through 4.14.x. Out of bounds event channels are ...
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in
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-gff7-q4h3-6x9j: An issue was discovered in Xen through 4
ghsa_unreviewed·2022-05-24
CVE-2020-25600 [MEDIUM] CWE-119 GHSA-gff7-q4h3-6x9j: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in
OSV
CVE-2020-25600: An issue was discovered in Xen through 4
osv·2020-09-23·CVSS 5.5
CVE-2020-25600 [MEDIUM] CVE-2020-25600: An issue was discovered in Xen through 4
An issue was discovered in Xen through 4.14.x. Out of bounds event channels are available to 32-bit x86 domains. The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly. Due to this misbehavior in
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342) [fedora-all]
bugzilla·2020-09-22·CVSS 5.5
CVE-2020-25600 [MEDIUM] CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342) [fedora-all]
CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342) [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 m
Bugzilla
CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342)
bugzilla·2020-09-17·CVSS 5.5
CVE-2020-25600 [MEDIUM] CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342)
CVE-2020-25600 xen: out of bounds event channels available to 32-bit x86 domains (XSA-342)
The so called 2-level event channel model imposes different limits on the number of usable event channels for 32-bit x86 domains vs 64-bit or Arm (either bitness) ones. 32-bit x86 domains can use only 1023 channels, due to limited space in their shared (between guest and Xen) information structure, whereas all other domains can use up to 4095 in this model. The recording of the respective limit during domain initialization, however, has occurred at a time where domains are still deemed to be 64-bit ones, prior to actually honoring respective domain properties. At the point domains get recognized as 32-bit ones, the limit didn't get updated accordingly.
Due to this misbehavior in Xen, 32-bit domains
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-342.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-342.html
2020-09-23
Published