CVE-2021-3527

Severity Score

5.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB packets are combined into a single, large transfer request, to reduce the overhead and improve performance. The combined size of the bulk transfer is used to dynamically allocate a variable length array (VLA) on the stack without proper validation. Since the total size is not bounded, a malicious guest could use this flaw to influence the array length and cause the QEMU process to perform an excessive allocation on the stack, resulting in a denial of service.

Se encontró un fallo en el dispositivo redirector USB (usb-redir) de QEMU. Los paquetes USB pequeños son combinados en una única petición de transferencia grande para reducir la sobrecarga y mejorar el rendimiento. El tamaño combinado de la transferencia masiva es usado para asignar dinámicamente una matriz de longitud variable (VLA) en la pila sin la comprobación apropiada. Dado que el tamaño total no está limitado, un huésped malicioso podría usar este fallo para influir en la longitud de la matriz y causar a un proceso QEMU llevar a cabo una asignación excesiva en la pila, resultando en una denegación de servicio

*Credits: N/A

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Local

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-04-30 CVE Reserved
2021-05-26 CVE Published
2023-03-08 EPSS Updated
2024-08-03 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-770: Allocation of Resources Without Limits or Throttling

CAPEC

References (8)

URL	Tag	Source
https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html	Mailing List
https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html	Mailing List
https://security.netapp.com/advisory/ntap-20210708-0008	Third Party Advisory

URL	Date	SRC

URL	Date	SRC
https://bugzilla.redhat.com/show_bug.cgi?id=1955695	2022-09-30
https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524c	2022-09-30
https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986	2022-09-30
https://www.openwall.com/lists/oss-security/2021/05/05/5	2022-09-30

URL	Date	SRC
https://security.gentoo.org/glsa/202208-27	2022-09-30

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Qemu Search vendor "Qemu"		Qemu Search vendor "Qemu" for product "Qemu"				<= 6.0.0 Search vendor "Qemu" for product "Qemu" and version " <= 6.0.0"		-		Affected
Redhat Search vendor "Redhat"		Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"				8.0 Search vendor "Redhat" for product "Enterprise Linux" and version "8.0"		-		Affected
Redhat Search vendor "Redhat"		Enterprise Linux Search vendor "Redhat" for product "Enterprise Linux"				8.0 Search vendor "Redhat" for product "Enterprise Linux" and version "8.0"		advanced_virtualization		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
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