SB2020102974 - Fedora 31 update for xen
Published: October 29, 2020 Updated: April 25, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Buffer overflow (CVE-ID: CVE-2020-27674)
The vulnerability allows a local authenticated user to read and manipulate data.
An issue was discovered in Xen through 4.14.x allowing x86 PV guest OS users to gain guest OS privileges by modifying kernel memory contents, because invalidation of TLB entries is mishandled during use of an INVLPG-like attack technique.
2) Insufficient verification of data authenticity (CVE-ID: CVE-2020-27670)
The vulnerability allows a local authenticated user to execute arbitrary code.
An issue was discovered in Xen through 4.14.x allowing x86 guest OS users to cause a denial of service (data corruption), cause a data leak, or possibly gain privileges because an AMD IOMMU page-table entry can be half-updated.
3) Improper Privilege Management (CVE-ID: CVE-2020-27671)
The vulnerability allows a local user to escalate privileges.
The vulnerability exists due to improper privilege management within the IOMMU TLB implementation. A local user on a guest OS can escalate privileges on the system by running a specially crafted application.
4) Race condition (CVE-ID: CVE-2020-27672)
The vulnerability allows a local authenticated user to execute arbitrary code.
An issue was discovered in Xen through 4.14.x allowing x86 guest OS users to cause a host OS denial of service, achieve data corruption, or possibly gain privileges by exploiting a race condition that leads to a use-after-free involving 2MiB and 1GiB superpages.
Remediation
Install update from vendor's website.