// For flags

CVE-2021-28702

Gentoo Linux Security Advisory 202208-23

Severity Score

7.6
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption.

Unos Dispositivos PCI con RMRRs no desasignados correctamente Determinados dispositivos PCI de un sistema pueden tener asignadas Regiones de Memoria Reservada (especificadas por medio de Informes de Regiones de Memoria Reservada, "RMRR"). Normalmente son usados para tareas de plataforma como la emulación USB heredada. Si un dispositivo de este tipo se pasa a un huésped, entonces al apagar el huésped el dispositivo no se desasigna correctamente. La configuración de IOMMU para estos dispositivos que no son desasignados correctamente termina apuntando a una estructura de datos liberada, incluyendo las Tablas de Página IO. Las subsiguientes DMA o interrupciones del dispositivo tendrán un comportamiento impredecible, que va desde fallos de IOMMU hasta corrupción de memoria

An update that fixes 7 vulnerabilities is now available. This update for xen fixes the following issues. Fixed PCI devices with RMRRs not deassigned correctly. Fixed PoD operations on misaligned GFNs. Fixed issues with partially successful P2M updates on x86. Fixed guests may exceed their designated memory limit. This update was imported from the SUSE:SLE-15-SP2:Update update project.

*Credits: N/A
CVSS Scores
Attack Vector
Physical
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-03-18 CVE Reserved
  • 2021-10-06 CVE Published
  • 2024-08-03 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-269: Improper Privilege Management
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Xen
Search vendor "Xen"
 Xen
Search vendor "Xen" for product "Xen"
 >= 4.13.0 <= 4.15.1
Search vendor "Xen" for product "Xen" and version " >= 4.13.0 <= 4.15.1"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 33
Search vendor "Fedoraproject" for product "Fedora" and version "33"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 34
Search vendor "Fedoraproject" for product "Fedora" and version "34"
-
Affected
Fedoraproject
Search vendor "Fedoraproject"
 Fedora
Search vendor "Fedoraproject" for product "Fedora"
 35
Search vendor "Fedoraproject" for product "Fedora" and version "35"
-
Affected
Debian
Search vendor "Debian"
 Debian Linux
Search vendor "Debian" for product "Debian Linux"
 9.0
Search vendor "Debian" for product "Debian Linux" and version "9.0"
-
Affected