CVE-2020-15564
Fixed in a distro release EPSS <1%
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.
Products: xen, debian_linux, fedoraproject fedora
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.10 | xen | 4.12.3-r2 |
| Alpine 3.11 | xen | 4.13.1-r2 |
| Alpine 3.12 | xen | 4.13.1-r2 |
| Alpine 3.13 | xen | 4.13.1-r4 |
| Alpine 3.14 | xen | 4.13.1-r4 |
| Alpine 3.15 | xen | 4.13.1-r4 |
| Alpine 3.16 | xen | 4.13.1-r4 |
| Alpine 3.17 | xen | 4.13.1-r4 |
| Alpine 3.18 | xen | 4.13.1-r4 |
| Alpine 3.19 | xen | 4.13.1-r4 |
| Alpine 3.20 | xen | 4.13.1-r4 |
| Alpine 3.21 | xen | 4.13.1-r4 |
| Alpine 3.22 | xen | 4.13.1-r4 |
| Alpine 3.23 | xen | 4.13.1-r4 |
| Alpine 3.24 | xen | 4.13.1-r4 |
| Alpine 3.9 | xen | 4.11.4-r0 |
| Debian 10 | xen | 4.11.4+24-gddaaccbbab-1~deb10u1 |
| Debian 12 | xen | 4.11.4+24-gddaaccbbab-1 |
| Debian 13 | xen | 4.11.4+24-gddaaccbbab-1 |
| Debian 14 | xen | 4.11.4+24-gddaaccbbab-1 |
| Ubuntu 16.04 LTS | xen | no fix |
| Ubuntu 18.04 LTS | xen | no fix |
| Ubuntu 20.04 LTS | xen | 4.11.3+24-g14b62ab3e5-1ubuntu2.3 |