CVE-2021-28695
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
0Exploited in Wild
-Decision
Descriptions
IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Both AMD and Intel allow ACPI tables to specify regions of memory which should be left untranslated, which typically means these addresses should pass the translation phase unaltered. While these are typically device specific ACPI properties, they can also be specified to apply to a range of devices, or even all devices. On all systems with such regions Xen failed to prevent guests from undoing/replacing such mappings (CVE-2021-28694). On AMD systems, where a discontinuous range is specified by firmware, the supposedly-excluded middle range will also be identity-mapped (CVE-2021-28695). Further, on AMD systems, upon de-assigment of a physical device from a guest, the identity mappings would be left in place, allowing a guest continued access to ranges of memory which it shouldn't have access to anymore (CVE-2021-28696).
Problemas de mapeo de páginas IOMMU en x86 [Este registro de inmaneración CNA se relaciona con múltiples CVEs; el texto explica qué aspectos/vulnerabilidades corresponden a cada CVE]. Tanto AMD como Intel permiten que las tablas ACPI especifiquen regiones de memoria que deben dejarse sin traducir, lo que normalmente significa que estas direcciones deben pasar la fase de traducción sin ser alteradas. Mientras que estas son típicamente propiedades ACPI específicas del dispositivo, también pueden ser especificadas para aplicarse a un rango de dispositivos, o incluso a todos los dispositivos. En todos los sistemas con tales regiones, Xen falló al evitar que los huéspedes deshicieran/reemplazaran tales mapeos (CVE-2021-28694). En los sistemas AMD, donde un rango discontinuo es especificado por el firmware, el rango medio supuestamente excluido también será mapeado por la identidad (CVE-2021-28695). Además, en los sistemas AMD, al desasignar un dispositivo físico de un huésped, los mapeos de identidad se dejarían en su lugar, permitiendo a un huésped el acceso continuo a rangos de memoria a los que ya no debería tener acceso (CVE-2021-28696).
CVSS Scores
SSVC
- Decision:-
Timeline
- 2021-03-18 CVE Reserved
- 2021-08-27 CVE Published
- 2024-05-12 EPSS Updated
- 2024-08-03 CVE Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
- ---------- First Exploit
CWE
CAPEC
References (9)
| URL | Tag | Source |
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| http://www.openwall.com/lists/oss-security/2021/09/01/1 | Mailing List |
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| http://www.openwall.com/lists/oss-security/2021/09/01/5 | Mailing List |
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| http://www.openwall.com/lists/oss-security/2021/09/01/6 | Mailing List |
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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" | * | - |
Affected
| ||||||
| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 33 Search vendor "Fedoraproject" for product "Fedora" and version "33" | - |
Affected
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| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 34 Search vendor "Fedoraproject" for product "Fedora" and version "34" | - |
Affected
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| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 35 Search vendor "Fedoraproject" for product "Fedora" and version "35" | - |
Affected
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| Debian Search vendor "Debian" | Debian Linux Search vendor "Debian" for product "Debian Linux" | 10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0" | - |
Affected
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