CVE-2021-28696
CVSS V2 Medium 4.6
CVSS V3 Medium 6.8
Description
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).
Overview
- CVE ID
- CVE-2021-28696
- Assigner
- security@xen.org
- Vulnerability Status
- Analyzed
- Published Version
- 2021-08-27T19:15:07
- Last Modified Date
- 2022-09-28T19:56:53
Weakness Enumerations
CPE Configuration (Product)
| CPE | Vulnerable | Operator | Version Start | Version End |
|---|---|---|---|---|
| cpe:2.3:o:xen:xen:*:*:*:*:*:*:*:* | 1 | OR | ||
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 1 | OR | ||
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 1 | OR | ||
| cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:* | 1 | OR | ||
| cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* | 1 | OR |
CVSS Version 2
- Version
- 2.0
- Vector String
- AV:L/AC:L/Au:N/C:P/I:P/A:P
- Access Vector
- LOCAL
- Access Compatibility
- LOW
- Authentication
- NONE
- Confidentiality Impact
- PARTIAL
- Integrity Impact
- PARTIAL
- Availability Impact
- PARTIAL
- Base Score
- 4.6
- Severity
- MEDIUM
- Exploitability Score
- 3.9
- Impact Score
- 6.4
CVSS Version 3
- Version
- 3.1
- Vector String
- CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Attack Vector
- PHYSICAL
- Attack Compatibility
- LOW
- Privileges Required
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality Impact
- HIGH
- Availability Impact
- HIGH
- Base Score
- 6.8
- Base Severity
- MEDIUM
- Exploitability Score
- 0.9
- Impact Score
- 5.9
References
| Reference URL | Reference Tags |
|---|---|
| http://www.openwall.com/lists/oss-security/2021/09/01/1 | Mailing List Third Party Advisory |
| http://www.openwall.com/lists/oss-security/2021/09/01/5 | Mailing List Third Party Advisory |
| http://www.openwall.com/lists/oss-security/2021/09/01/6 | Mailing List Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2VQCFAPBNGBBAOMJZG6QBREOG5IIDZID/ | Mailing List Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FZCNPSRPGFCQRYE2BI4D4Q4SCE56ANV2/ | Mailing List Third Party Advisory |
| https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LPRVHW4J4ZCPPOHZEWP5MOJT7XDGFFPJ/ | Mailing List Third Party Advisory |
| https://security.gentoo.org/glsa/202208-23 | Third Party Advisory |
| https://www.debian.org/security/2021/dsa-4977 | Third Party Advisory |
| https://xenbits.xenproject.org/xsa/advisory-378.txt | Vendor Advisory |
Sources
| Source Name | Source URL |
|---|---|
| NIST | https://nvd.nist.gov/vuln/detail/CVE-2021-28696 |
| MITRE | https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28696 |
History
| Created | Old Value | New Value | Data Type | Notes |
|---|---|---|---|---|
| 2022-05-10 06:41:19 | Added to TrackCVE | |||
| 2022-12-05 09:12:29 | 2021-08-27T19:15Z | 2021-08-27T19:15:07 | CVE Published Date | updated |
| 2022-12-05 09:12:29 | 2022-09-28T19:56:53 | CVE Modified Date | updated | |
| 2022-12-05 09:12:29 | Analyzed | Vulnerability Status | updated | |
| 2022-12-05 09:12:33 | References | updated |