AMD: Out-of-bounds Read (CVE-2024-21963)

What is affected, what to do

An out-of-bounds read vulnerability in the IOMMU could allow a malicious guest to corrupt hypervisor (HV) pages and potentially cause a host crash leading to loss of availability.

The available sources name no fixed version. Check the vendor guidance in the references below.

Affected

• open source Xen = 4.20.x..4.20.x
• open source Xen = 4.19.x..4.19.x
• open source Xen = 4.18.x..4.18.x
• open source Xen = 4.17.x..4.17.x
• open source Xen = 4.21.x..4.21.x
• AMD Prozessor = EPYC..EPYC
• AMD Prozessor = Instinct MI300A..Instinct MI300A
• AMD Prozessor = Ryzen..Ryzen
• AMD Radeon = Graphics Driver..Graphics Driver
• AMD Prozessor = Athlon..Athlon

Not sure whether and how you are affected? Ask a question about this vulnerability

Metrics

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2

NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

Read in glossary

Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.

CRA

The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

Read in glossary

From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.

ISO/IEC 27001

ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

Read in glossary

Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

An out-of-bounds read vulnerability in the IOMMU could allow a malicious guest to corrupt hypervisor (HV) pages and potentially cause a host crash leading to loss of availability.

Source: BSI WID Portal, BSI CSAF, NVD (NIST), cvelistv5, ENISA EUVD, HKCERT (CC BY 3.0 HK) · HKCERT rating: medium

Vendors and products

• AMD Amd Epyc™ 4004 Series Processors
• AMD Amd Epyc™ 4005 Series Processors
• AMD Amd Epyc™ 7001 Series Processors
• AMD Amd Epyc™ 7002 Series Processors
• AMD Amd Epyc™ 7003 Series Processors
• AMD Amd Epyc™ 8004 Series Processors
• AMD Amd Epyc™ 8005 Series Processors
• AMD Amd Epyc™ 9004 Series Processors
• AMD Amd Epyc™ 9005 Series Processors
• AMD Amd Epyc™ Embedded 3000 Series Processors
• AMD Amd Epyc™ Embedded 7002 Series Processors
• AMD Amd Epyc™ Embedded 7003 Series Processors

Weakness classes (CWE)

• CWE-125Out-of-bounds Read

  Base

  The product reads data past the end, or before the beginning, of the intended buffer.

  Entry at MITRE CWE-125

References & sources

• amd.comen/resources/product-security/bulletin/AMD-SB-4018.htmleuvd
• amd.comen/resources/product-security/bulletin/AMD-SB-3060.htmleuvd
• openwall.comlists/oss-security/2026/11/10/21euvd
• xenbits.xen.orgxsa/advisory-524.htmleuvd
• NVD (NIST)vuln/detail/CVE-2024-21963euvd

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

1. 13.11.2026Record modifiedCISA ADP

   CISA assessment (SSVC): exploitation: none known, automatable: no

   Show the original change

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   SSVC assessment	added	—	{"id":"CVE-2024-21963","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-11-13T00:15:56.802266Z"}

   Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

2. 12.11.2026Receivedamd.com

   CVSS V4.0: AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

   Weakness type: CWE-125

   Description added or changed

   New references:

   • https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-3060.html
   • https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-4018.html
   Show 6 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   Description	added	—	An out-of-bounds read vulnerability in the IOMMU could allow a malicious guest to corrupt hypervisor (HV) pages and potentially cause a host crash leading to loss of availability.
   CVSS	added	—	AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
   Weakness type (CWE)	added	—	CWE-125
   Affected versions (publisher)	added	—	New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2024/21xxx/CVE-2024-21963.json">CVE-2024-21963</a>
   Reference	added	—	https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-3060.html
   Reference	added	—	https://www.amd.com/en/resources/product-security/bulletin/AMD-SB-4018.html

   Source identifier: psirt@amd.com

3. 12.11.2026Record modifiedCVE Program

   New references:

   • http://www.openwall.com/lists/oss-security/2026/11/10/21
   • http://xenbits.xen.org/xsa/advisory-524.html
   Show 2 original changes

   Individual changes of this event as published by NVD

   Type	Action	Before	After
   Reference	added	—	http://www.openwall.com/lists/oss-security/2026/11/10/21
   Reference	added	—	http://xenbits.xen.org/xsa/advisory-524.html

   Source identifier: af854a3a-2127-422b-91ae-364da2661108