Xen up to 4.14.x Superpage use after free

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CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

A vulnerability classified as problematic has been found in Xen up to 4.14.x (Virtualization Software). This affects an unknown code of the component Superpage Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-416. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The weakness was presented 10/23/2020. It is possible to read the advisory at xenbits.xen.org. This vulnerability is uniquely identified as CVE-2020-27672 since 10/22/2020. The attack needs to be initiated within the local network. A authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/26/2020).

Applying a patch is able to eliminate this problem.

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CPE 2.3infoedit

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CVSSv3infoedit

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.0
NVD Vector: 🔒

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

NVD Base Score: 🔒

Exploitinginfoedit

Class: Memory corruption
CWE: CWE-416
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfoedit

Threat: 🔍
Adversaries: 🔍
Geopolitics: 🔍
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Predictions: 🔍
Remediation: 🔍

Countermeasuresinfoedit

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfoedit

10/22/2020 CVE assigned
10/23/2020 +1 days Advisory disclosed
10/23/2020 +0 days VulDB entry created
11/26/2020 +34 days VulDB last update

Sourcesinfoedit

Advisory: xenbits.xen.org
Status: Confirmed

CVE: CVE-2020-27672 (🔒)

Entryinfoedit

Created: 10/23/2020 01:49 PM
Updated: 11/26/2020 03:11 PM
Changes: (18) vulnerability_cvss3_nvd_av vulnerability_cvss3_nvd_ac vulnerability_cvss3_nvd_pr vulnerability_cvss3_nvd_ui vulnerability_cvss3_nvd_s vulnerability_cvss3_nvd_c vulnerability_cvss3_nvd_i vulnerability_cvss3_nvd_a vulnerability_cvss2_nvd_av vulnerability_cvss2_nvd_ac vulnerability_cvss2_nvd_au vulnerability_cvss2_nvd_ci vulnerability_cvss2_nvd_ii vulnerability_cvss2_nvd_ai vulnerability_cvss3_meta_basescore vulnerability_cvss3_meta_tempscore vulnerability_cvss2_nvd_basescore vulnerability_cvss3_nvd_basescore
Complete: 🔍

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