CVE-2021-3527
published 2021-05-26CVE-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…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.37%
29.4th percentile
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.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | qemu | < qemu 1:5.2+dfsg-11 (bookworm) | qemu 1:5.2+dfsg-11 (bookworm) |
| msrc | cm1_qemu-kvm_4.2.0-33_on_cbl_mariner_1.0 | — | — |
| qemu | qemu | <= 6.0.0 | — |
| qemu | qemu | — | — |
| qemu | qemu | >= 0 < 1:5.2+dfsg-11 | 1:5.2+dfsg-11 |
| qemu | qemu | >= 0 < 1:5.2+dfsg-11 | 1:5.2+dfsg-11 |
| qemu | qemu | >= 0 < 1:5.2+dfsg-11 | 1:5.2+dfsg-11 |
| qemu | qemu | >= 0 < 1:5.2+dfsg-11 | 1:5.2+dfsg-11 |
| qemu | qemu | >= 0 < 1:2.11+dfsg-1ubuntu7.37 | 1:2.11+dfsg-1ubuntu7.37 |
| qemu | qemu | >= 0 < 1:4.2-3ubuntu6.17 | 1:4.2-3ubuntu6.17 |
| redhat | enterprise_linux | — | — |
| ubuntu | qemu | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvdv2.02.1LOWAV:L/AC:L/Au:N/C:N/I:N/A:P
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
vendor_ubuntu3.8LOW
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Ubuntu
QEMU regression
vendor_ubuntu·2026-06-28·CVSS 3.8
CVE-2020-11947 [LOW] QEMU regression
Title: QEMU regression
Summary: USN-8412-1 introduced a regression in QEMU
USN-8412-1 fixed vulnerabilities QEMU. On Ubuntu 20.04 LTS, the fix for
CVE-2024-4467 was incomplete and prevented the creation of boot volumes
from qcow2 images. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Felipe Franciosi, Raphael Norwitz, and Peter Turschmid discovered that the
iSCSI block driver in QEMU incorrectly handled certain responses from an
iSCSI server. A remote attacker could possibly use this issue to cause
QEMU to crash, resulting in a denial of service, or possibly execute
arbitrary code. This issue only affected Ubuntu 14.04 LTS. (CVE-2020-1711)
It was discovered that the iSCSI block driver in QEMU incorrectly handled
certain memory operations
Ubuntu
QEMU vulnerabilities
vendor_ubuntu·2026-06-09·CVSS 3.8
CVE-2021-3416 [LOW] QEMU vulnerabilities
Title: QEMU vulnerabilities
Summary: Several security issues were fixed in QEMU.
Felipe Franciosi, Raphael Norwitz, and Peter Turschmid discovered that the
iSCSI block driver in QEMU incorrectly handled certain responses from an
iSCSI server. A remote attacker could possibly use this issue to cause QEMU
to crash, resulting in a denial of service, or possibly execute arbitrary
code. This issue only affected Ubuntu 14.04 LTS. (CVE-2020-1711)
It was discovered that the iSCSI block driver in QEMU incorrectly handled
certain memory operations, leading to a heap-based buffer over-read. An
attacker could possibly use this issue to expose sensitive information from
the host. This issue only affected Ubuntu 14.04 LTS. (CVE-2020-11947)
Ziming Zhang discovered that the SM501 display driver in QEM
Ubuntu
QEMU vulnerabilities
vendor_ubuntu·2021-07-15·CVSS 2.3
CVE-2021-3594 [LOW] QEMU vulnerabilities
Title: QEMU vulnerabilities
Summary: Several security issues were fixed in QEMU.
Lei Sun discovered that QEMU incorrectly handled certain MMIO operations.
An attacker inside the guest could possibly use this issue to cause QEMU to
crash, resulting in a denial of service. (CVE-2020-15469)
Wenxiang Qian discovered that QEMU incorrectly handled certain ATAPI
commands. An attacker inside the guest could possibly use this issue to
cause QEMU to crash, resulting in a denial of service. This issue only
affected Ubuntu 21.04. (CVE-2020-29443)
Cheolwoo Myung discovered that QEMU incorrectly handled SCSI device
emulation. An attacker inside the guest could possibly use this issue to
cause QEMU to crash, resulting in a denial of service. (CVE-2020-35504,
CVE-2020-35505, CVE-2021-3392)
Alex Xu di
Microsoft
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
vendor_msrc·2021-05-11·CVSS 5.5
CVE-2021-3527 [MEDIUM] CWE-770 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
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up
Red Hat
QEMU: usb: unbounded stack allocation in usbredir
vendor_redhat·2021-04-30·CVSS 5.5
CVE-2021-3527 [MEDIUM] CWE-770 QEMU: usb: unbounded stack allocation in usbredir
QEMU: usb: unbounded stack allocation in usbredir
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.
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 t
Debian
CVE-2021-3527: qemu - A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB pac...
vendor_debian·2021·CVSS 5.5
CVE-2021-3527 [MEDIUM] CVE-2021-3527: qemu - A flaw was found in the USB redirector device (usb-redir) of QEMU. Small USB pac...
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.
Scope: local
bookworm: resolved (fixed in 1:5.2+dfsg-11)
bullseye: resolved (fixed in 1:5.2+dfsg-11)
forky: resolved (fixed in 1:5.2+dfsg-11)
sid: resolved (fixed in 1:5.2+dfsg-11)
trixie: resolved (fixed in 1:5.2+dfsg-11)
GHSA
GHSA-fwv2-775h-qv4v: A flaw was found in the USB redirector device (usb-redir) of QEMU
ghsa_unreviewed·2022-05-24
CVE-2021-3527 [MEDIUM] CWE-770 GHSA-fwv2-775h-qv4v: A flaw was found in the USB redirector device (usb-redir) of QEMU
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.
OSV
qemu vulnerabilities
osv·2021-07-15·CVSS 2.3
CVE-2020-15469 [LOW] qemu vulnerabilities
qemu vulnerabilities
Lei Sun discovered that QEMU incorrectly handled certain MMIO operations.
An attacker inside the guest could possibly use this issue to cause QEMU to
crash, resulting in a denial of service. (CVE-2020-15469)
Wenxiang Qian discovered that QEMU incorrectly handled certain ATAPI
commands. An attacker inside the guest could possibly use this issue to
cause QEMU to crash, resulting in a denial of service. This issue only
affected Ubuntu 21.04. (CVE-2020-29443)
Cheolwoo Myung discovered that QEMU incorrectly handled SCSI device
emulation. An attacker inside the guest could possibly use this issue to
cause QEMU to crash, resulting in a denial of service. (CVE-2020-35504,
CVE-2020-35505, CVE-2021-3392)
Alex Xu discovered that QEMU incorrectly handled the virtio-fs shared f
OSV
CVE-2021-3527: A flaw was found in the USB redirector device (usb-redir) of QEMU
osv·2021-05-26·CVSS 5.5
CVE-2021-3527 [MEDIUM] CVE-2021-3527: A flaw was found in the USB redirector device (usb-redir) of QEMU
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.redhat.com/show_bug.cgi?id=1955695https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524chttps://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986https://lists.debian.org/debian-lts-announce/2021/09/msg00000.htmlhttps://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlhttps://security.gentoo.org/glsa/202208-27https://security.netapp.com/advisory/ntap-20210708-0008/https://www.openwall.com/lists/oss-security/2021/05/05/5https://bugzilla.redhat.com/show_bug.cgi?id=1955695https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524chttps://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986https://lists.debian.org/debian-lts-announce/2021/09/msg00000.htmlhttps://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlhttps://security.gentoo.org/glsa/202208-27https://security.netapp.com/advisory/ntap-20210708-0008/https://www.openwall.com/lists/oss-security/2021/05/05/5
2021-05-26
Published