CVE-2021-20257
Estado: ModificadaMedia (6.5)—
An infinite loop flaw was found in the e1000 NIC emulator of the QEMU. This issue occurs while processing transmits (tx) descriptors in process_tx_desc if various descriptor fields are initialized with invalid values. This flaw allows a guest to consume CPU cycles on the host, resulting in a denial of service. The highest threat from this vulnerability is to system availability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.37%
- Percentil entre todas las CVEs puntuadas: 29
- Fecha de la puntuación: 6/10/2026
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 (8)
CWE
- CWE-835
- CWE-835
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1930087
- https://github.com/qemu/qemu/commit/3de46e6fc489c52c9431a8a832ad8170a7569bd8
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg07428.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20220425-0003/
- https://www.openwall.com/lists/oss-security/2021/02/25/2
- https://bugzilla.redhat.com/show_bug.cgi?id=1930087
- https://github.com/qemu/qemu/commit/3de46e6fc489c52c9431a8a832ad8170a7569bd8
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg07428.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20220425-0003/
- https://www.openwall.com/lists/oss-security/2021/02/25/2
JSON original (NVD)
Mostrar
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