CVE-2021-3527
Estado: ModificadaMedia (5.5)—
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
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
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: 7/10/2026
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 (3)
CWE
- CWE-770
- CWE-770
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1955695
- https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524c
- https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986
- https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20210708-0008/
- https://www.openwall.com/lists/oss-security/2021/05/05/5
- https://bugzilla.redhat.com/show_bug.cgi?id=1955695
- https://gitlab.com/qemu-project/qemu/-/commit/05a40b172e4d691371534828078be47e7fff524c
- https://gitlab.com/qemu-project/qemu/-/commit/7ec54f9eb62b5d177e30eb8b1cad795a5f8d8986
- https://lists.debian.org/debian-lts-announce/2021/09/msg00000.html
- https://lists.debian.org/debian-lts-announce/2022/09/msg00008.html
- https://security.gentoo.org/glsa/202208-27
- https://security.netapp.com/advisory/ntap-20210708-0008/
- https://www.openwall.com/lists/oss-security/2021/05/05/5
JSON original (NVD)
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