CVE-2021-3748
Estado: ModificadaAlta (7.5)—
A use-after-free vulnerability was found in the virtio-net device of QEMU. It could occur when the descriptor's address belongs to the non direct access region, due to num_buffers being set after the virtqueue elem has been unmapped. A malicious guest could use this flaw to crash QEMU, resulting in a denial of service condition, or potentially execute code on the host with the privileges of the QEMU process.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.52%
- Percentil entre todas las CVEs puntuadas: 42
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (6)
CWE
- CWE-416
- CWE-416
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1998514
- https://github.com/qemu/qemu/commit/bedd7e93d01961fcb16a97ae45d93acf357e11f6
- https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://lists.nongnu.org/archive/html/qemu-devel/2021-09/msg00388.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20220425-0004/
- https://ubuntu.com/security/CVE-2021-3748
- https://bugzilla.redhat.com/show_bug.cgi?id=1998514
- https://github.com/qemu/qemu/commit/bedd7e93d01961fcb16a97ae45d93acf357e11f6
- https://lists.debian.org/debian-lts-announce/2022/04/msg00002.html
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://lists.nongnu.org/archive/html/qemu-devel/2021-09/msg00388.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20220425-0004/
- https://ubuntu.com/security/CVE-2021-3748
JSON original (NVD)
Mostrar
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