CVE-2021-3527

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.

CVSS v3.0 5.5 MEDIUM
CVSS v2.0 2.1 LOW

5.5^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

2.1^/10

CVSS v2.0 : LOW

Vector : AV:L/AC:L/Au:N/C:N/I:N/A:P

Exploitability : 3.9 / Impact : 2.9

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://www.openwall.com/lists/oss-security/2021/05/05/5	Mailing List Patch Third Party Advisory
https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524c	Patch Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1955695	Issue Tracking Patch Third Party Advisory
https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986	Patch Third Party Advisory
https://security.netapp.com/advisory/ntap-20210708-0008/	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:redhat:enterprise_linux:8.0::::-:::
	cpe:2.3:o:redhat:enterprise_linux:8.0::::advanced_virtualization:::

Configuration 3 (hide)

cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

Information

Published : 2021-05-26 22:15

Updated : 2021-11-15 17:22

NVD link : CVE-2021-3527

Mitre link : CVE-2021-3527

JSON object : View

Products Affected

redhat

enterprise_linux

debian

debian_linux

qemu

qemu

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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