CVE-2020-15564
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor...
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
CVE-2020-15564- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - CVSS 2.0
- 4.9 Medium
AV:L/AC:L/Au:N/C:N/I:N/A:C - Weakness
- CWE-119
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
CVE-2020-15564- Updated
- 2026-11-02
EUVDEUVD-2020-7551 No score
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
EUVD-2020-7551- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-m5jw-hjp2-vr52
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor...
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
GHSA-m5jw-hjp2-vr52- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - Weakness
- CWE-20, CWE-119
- Updated
- 2026-11-02
OSVALPINE-CVE-2020-15564
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
ALPINE-CVE-2020-15564- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-02
OSV
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
CVE-2020-15564- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2020-15564
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
DEBIAN-CVE-2020-15564- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2020-15564
6.5
An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
- Record
UBUNTU-CVE-2020-15564- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUSN-5617-1 No score
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 service or possibly gain privileges. (CVE-2020-11740, CVE-2020-11741)
It was discovered that Xen incorrectly handled grant tables. A malicious guest could possibly use this issue to cause a denial of service. (CVE-2020-11742, CVE-2020-11743)
Jan Beulich discovered that Xen incorrectly handled certain code paths. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-15563)
Julien Grall discovered that Xen incorrectly verified memory addresses provided by the guest on ARM-based systems. A malicious guest administrator could possibly use this issue to cause a denial of service. (CVE-2020-15564)
Roger Pau Monné discovered that Xen incorrectly handled caching on x86 Intel systems. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-15565)
It was discovered that Xen incorrectly handled error in event-channel port allocation. A malicious guest could possibly use this issue to cause a denial of service. (CVE-2020-15566)
Jan Beulich discovered that Xen incorrectly handled certain EPT (Extended Page Tables). An attacker could possibly use this issue to cause a denial of service, data corruption or privilege escalation. (CVE-2020-15567)
Andrew Cooper discovered that Xen incorrectly handled PCI passthrough. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25595)
Andrew Cooper discovered that Xen incorrectly sanitized path injections. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25596)
Jan Beulich discovered that Xen incorrectly handled validation of event channels. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25597)
Julien Grall and Jan Beulich discovered that Xen incorrectly handled resetting event channels. An attacker could possibly use this issue to cause a denial of service or obtain sensitive information. (CVE-2020-25599)
Julien Grall discovered that Xen incorrectly handled event channels memory allocation on 32-bits domains. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25600)
Jan Beulich discovered that Xen incorrectly handled resetting or cleaning up event channels. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25601)
Andrew Cooper discovered that Xen incorrectly handled certain Intel specific MSR (Model Specific Registers). An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25602)
Julien Grall discovered that Xen incorrectly handled accessing/allocating event channels. An attacker could possibly use this issue to cause a denial of service, obtain sensitive information of privilege escalation. (CVE-2020-25603)
Igor Druzhinin discovered that Xen incorrectly handled locks. An attacker could possibly use this issue to cause a denial of service. (CVE-2020-25604)
- Record
USN-5617-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
xenAlpine:v3.10 |
4.8.0 up to 4.12.3-r2 | 4.12.3-r2 |
xenAlpine:v3.11 |
4.8.0 up to 4.13.1-r2 | 4.13.1-r2 |
xenAlpine:v3.12 |
4.8.0 up to 4.13.1-r2 | 4.13.1-r2 |
xenAlpine:v3.13 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.14 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.15 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.16 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.17 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.18 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.19 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
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| Package | Affected | Fixed |
|---|---|---|
xenAlpine:v3.20 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.21 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.22 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.23 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.24 |
4.8.0 up to 4.13.1-r4 | 4.13.1-r4 |
xenAlpine:v3.9 |
4.8.0 up to 4.11.4-r0 | 4.11.4-r0 |
xenDebian:12 |
before 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
xenDebian:13 |
before 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
xenDebian:14 |
before 4.11.4+24-gddaaccbbab-1 | 4.11.4+24-gddaaccbbab-1 |
xenDebian:10 From an advisory covering 10 CVEs |
before 4.11.4+24-gddaaccbbab-1~deb10u1, plus listed versions 4.11.1+92-g6c33308a8d-24.11.3+24-g14b62ab3e5-14.11.3+24-g14b62ab3e5-1~deb10u14.11.4-1 |
4.11.4+24-gddaaccbbab-1~deb10u1 |
xenUbuntu:16.04:LTS |
All versions, plus listed versions 4.5.1-0ubuntu14.5.1-0ubuntu24.6.0-1ubuntu14.6.0-1ubuntu24.6.0-1ubuntu4 Show 7 moreShow less4.6.0-1ubuntu4.14.6.0-1ubuntu4.24.6.0-1ubuntu4.34.6.5-0ubuntu14.6.5-0ubuntu1.14.6.5-0ubuntu1.24.6.5-0ubuntu1.4 |
None known |
xenUbuntu:18.04:LTS |
All versions, plus listed versions 4.9.0-0ubuntu34.9.0-0ubuntu44.9.2-0ubuntu1 |
None known |
xenUbuntu:20.04:LTS |
before 4.11.3+24-g14b62ab3e5-1ubuntu2.3, plus listed versions 4.9.2-0ubuntu24.9.2-0ubuntu64.9.2-0ubuntu74.11.3+24-g14b62ab3e5-1ubuntu14.11.3+24-g14b62ab3e5-1ubuntu24.11.3+24-g14b62ab3e5-1ubuntu2.2 |
4.11.3+24-g14b62ab3e5-1ubuntu2.3 |
xenUbuntu:20.04:LTS From an advisory covering 20 CVEs |
before 4.11.3+24-g14b62ab3e5-1ubuntu2.3, plus listed versions 4.9.2-0ubuntu24.9.2-0ubuntu64.9.2-0ubuntu74.11.3+24-g14b62ab3e5-1ubuntu14.11.3+24-g14b62ab3e5-1ubuntu24.11.3+24-g14b62ab3e5-1ubuntu2.2 |
4.11.3+24-g14b62ab3e5-1ubuntu2.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-15564 is a medium vulnerability (CVSS 6.5) in Xen, published July 7, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.40%, the 34th percentile. Fixed in xen 4.12.3-r2.
References
xenbits.xen.org/xsa/advisory-327.html
openwall.com/lists/oss-security/2020/07/07/5
debian.org/security/2020/dsa-4723
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH
security.gentoo.org/glsa/202007-02
Show 28 moreShow less
nvd.nist.gov/vuln/detail/CVE-2020-15564
lists.fedoraproject.org/archives/list/[email protected]/message/MXESCOVI7AVRNC7HEAMFM7PMEO6D3AUH
lists.fedoraproject.org/archives/list/[email protected]/message/VB3QJJZV23Z2IDYEMIHELWYSQBUEW6JP
github.com/advisories/GHSA-m5jw-hjp2-vr52
security.alpinelinux.org/vuln/CVE-2020-15564
security-tracker.debian.org/tracker/CVE-2020-15564
ubuntu.com/security/CVE-2020-15564
ubuntu.com/security/notices/USN-5617-1
cve.org/CVERecord?id=CVE-2020-15564
ubuntu.com/security/CVE-2020-0543
ubuntu.com/security/CVE-2020-11739
ubuntu.com/security/CVE-2020-11740
ubuntu.com/security/CVE-2020-11741
ubuntu.com/security/CVE-2020-11742
ubuntu.com/security/CVE-2020-11743
ubuntu.com/security/CVE-2020-15563
ubuntu.com/security/CVE-2020-15565
ubuntu.com/security/CVE-2020-15566
ubuntu.com/security/CVE-2020-15567
ubuntu.com/security/CVE-2020-25595
ubuntu.com/security/CVE-2020-25596
ubuntu.com/security/CVE-2020-25597
ubuntu.com/security/CVE-2020-25599
ubuntu.com/security/CVE-2020-25600
ubuntu.com/security/CVE-2020-25601
ubuntu.com/security/CVE-2020-25602
ubuntu.com/security/CVE-2020-25603
ubuntu.com/security/CVE-2020-25604