Xen on AMD64 Debug Mask denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Xen on AMD64 and classified as critical. This affects an unknown function of the component Debug Mask Handler. Such manipulation leads to denial of service. This vulnerability is referenced as CVE-2023-34327. No exploit is available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Xen on AMD64 (Virtualization Software) (the affected version is unknown) and classified as critical. Affected by this issue is an unknown code of the component Debug Mask Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

[This CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] AMD CPUs since ~2014 have extensions to normal x86 debugging functionality. Xen supports guests using these extensions. Unfortunately there are errors in Xen's handling of the guest state, leading to denials of service. 1) CVE-2023-34327 - An HVM vCPU can end up operating in the context of a previous vCPUs debug mask state. 2) CVE-2023-34328 - A PV vCPU can place a breakpoint over the live GDT. This allows the PV vCPU to exploit XSA-156 / CVE-2015-8104 and lock up the CPU entirely.

The weakness was published 10/10/2023. The advisory is shared for download at seclists.org. This vulnerability is handled as CVE-2023-34327 since 06/01/2023. There are neither technical details nor an exploit publicly available.

Applying a patch is able to eliminate this problem.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/01/2023 🔍
10/10/2023 +131 days 🔍
10/10/2023 +0 days 🔍
06/03/2025 +602 days 🔍

Sourcesinfo

Advisory: seclists.org
Status: Confirmed

CVE: CVE-2023-34327 (🔍)
GCVE (CVE): GCVE-0-2023-34327
GCVE (VulDB): GCVE-100-241700

Entryinfo

Created: 10/10/2023 16:41
Updated: 06/03/2025 19:39
Changes: 10/10/2023 16:41 (38), 06/03/2025 19:39 (27)
Complete: 🔍
Cache ID: 216::103

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