CVE-2021-4207
published 2022-04-29CVE-2021-4207: A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can…
PriorityP339high8.2CVSS 3.1
AVLACLPRHUINSCCHIHAH
EPSS
0.40%
33.3th percentile
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
Affected
23 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | debian_linux | — | — |
| debian | qemu | < qemu 1:7.0+dfsg-1 (bookworm) | qemu 1:7.0+dfsg-1 (bookworm) |
| msrc | azl3_qemu_6.2.0-18_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_qemu_6.2.0-13_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| msrc | cm1_qemu-kvm_4.2.0-48_on_cbl_mariner_1.0 | — | — |
| qemu | qemu | < 7.0.0 | 7.0.0 |
| qemu | qemu | — | — |
| qemu | qemu | >= 0 < 1:5.2+dfsg-11+deb11u2 | 1:5.2+dfsg-11+deb11u2 |
| qemu | qemu | >= 0 < 1:7.0+dfsg-1 | 1:7.0+dfsg-1 |
| qemu | qemu | >= 0 < 1:7.0+dfsg-1 | 1:7.0+dfsg-1 |
| qemu | qemu | >= 0 < 1:7.0+dfsg-1 | 1:7.0+dfsg-1 |
| qemu | qemu | >= 0 < 1:2.11+dfsg-1ubuntu7.40 | 1:2.11+dfsg-1ubuntu7.40 |
| qemu | qemu | >= 0 < 1:4.2-3ubuntu6.23 | 1:4.2-3ubuntu6.23 |
| qemu | qemu | >= 0 < 1:6.2+dfsg-2ubuntu6.2 | 1:6.2+dfsg-2ubuntu6.2 |
| redhat | enterprise_linux | — | — |
| ubuntu | qemu | — | — |
CVSS provenance
nvdv3.18.2HIGHCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv8.2HIGH
vendor_debian8.2HIGH
vendor_msrc8.2HIGH
vendor_redhat8.2HIGH
vendor_ubuntu6.1MEDIUM
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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·2022-06-21·CVSS 6.1
CVE-2022-26354 [MEDIUM] QEMU vulnerabilities
Title: QEMU vulnerabilities
Summary: Several security issues were fixed in QEMU.
Alexander Bulekov discovered that QEMU incorrectly handled floppy disk
emulation. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a denial of service, or possibly leak
sensitive information. (CVE-2021-3507)
It was discovered that QEMU incorrectly handled NVME controller emulation.
An attacker inside the guest could use this issue to cause QEMU to crash,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 22.04 LTS. (CVE-2021-3929)
It was discovered that QEMU incorrectly handled QXL display device
emulation. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a deni
Microsoft
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor
vendor_msrc·2022-04-12·CVSS 8.2
CVE-2021-4207 [HIGH] CWE-362 A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
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 to date with the most recent and most secure versions of the open source libraries with which the distro is
Red Hat
QEMU: QXL: double fetch in qxl_cursor() can lead to heap buffer overflow
vendor_redhat·2022-03-28·CVSS 8.2
CVE-2021-4207 [HIGH] CWE-362 QEMU: QXL: double fetch in qxl_cursor() can lead to heap buffer overflow
QEMU: QXL: double fetch in qxl_cursor() can lead to heap buffer overflow
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user c
Debian
CVE-2021-4207: qemu - A flaw was found in the QXL display device emulation in QEMU. A double fetch of ...
vendor_debian·2021·CVSS 8.2
CVE-2021-4207 [HIGH] CVE-2021-4207: qemu - A flaw was found in the QXL display device emulation in QEMU. A double fetch of ...
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
Scope: local
bookworm: resolved (fixed in 1:7.0+dfsg-1)
bullseye: resolved (fixed in 1:5.2+dfsg-11+deb11u2)
forky: resolved (fixed in 1:7.0+dfsg-1)
sid: resolved (fixed in 1:7.0+dfsg-1)
trixie: resolved (fixed in 1:7.0+dfsg-1)
OSV
qemu vulnerabilities
osv·2022-06-21·CVSS 6.1
CVE-2021-3507 [MEDIUM] qemu vulnerabilities
qemu vulnerabilities
Alexander Bulekov discovered that QEMU incorrectly handled floppy disk
emulation. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a denial of service, or possibly leak
sensitive information. (CVE-2021-3507)
It was discovered that QEMU incorrectly handled NVME controller emulation.
An attacker inside the guest could use this issue to cause QEMU to crash,
resulting in a denial of service, or possibly execute arbitrary code. This
issue only affected Ubuntu 22.04 LTS. (CVE-2021-3929)
It was discovered that QEMU incorrectly handled QXL display device
emulation. A privileged attacker inside the guest could use this issue to
cause QEMU to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2021-
GHSA
GHSA-9p8r-v33g-4939: A flaw was found in the QXL display device emulation in QEMU
ghsa_unreviewed·2022-04-30
CVE-2021-4207 [HIGH] CWE-120 GHSA-9p8r-v33g-4939: A flaw was found in the QXL display device emulation in QEMU
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
OSV
CVE-2021-4207: A flaw was found in the QXL display device emulation in QEMU
osv·2022-04-29·CVSS 8.2
CVE-2021-4207 [HIGH] CVE-2021-4207: A flaw was found in the QXL display device emulation in QEMU
A flaw was found in the QXL display device emulation in QEMU. A double fetch of guest controlled values `cursor->header.width` and `cursor->header.height` can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. A malicious privileged guest user could use this flaw to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://bugzilla.redhat.com/show_bug.cgi?id=2036966https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlhttps://security.gentoo.org/glsa/202208-27https://starlabs.sg/advisories/21-4207/https://www.debian.org/security/2022/dsa-5133https://bugzilla.redhat.com/show_bug.cgi?id=2036966https://lists.debian.org/debian-lts-announce/2022/09/msg00008.htmlhttps://security.gentoo.org/glsa/202208-27https://security.netapp.com/advisory/ntap-20250321-0009/https://starlabs.sg/advisories/21-4207/https://www.debian.org/security/2022/dsa-5133
2022-04-29
Published