CVE-2021-3448
Estado: ModificadaMedia (4)—
A flaw was found in dnsmasq in versions before 2.85. When configured to use a specific server for a given network interface, dnsmasq uses a fixed port while forwarding queries. An attacker on the network, able to find the outgoing port used by dnsmasq, only needs to guess the random transmission ID to forge a reply and get it accepted by dnsmasq. This flaw makes a DNS Cache Poisoning attack much easier. The highest threat from this vulnerability is to data integrity.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
- Puntuación base: 4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 2.28%
- Percentil entre todas las CVEs puntuadas: 83
- 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 (4)
CWE
- CWE-358
- NVD-CWE-Other
Referencias
- https://bugzilla.redhat.com/show_bug.cgi?id=1939368
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/
- https://security.gentoo.org/glsa/202105-20
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://bugzilla.redhat.com/show_bug.cgi?id=1939368
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVTJUOFFFHINLKWAOC2ZSC5MOPD4SJ24/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FHG7GWSQWKF7JXIMLOGJBKZWBB4VIAJ7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GHURNEHHUBSW45KMIZ4FNBCSUPWPGV5V/
- https://security.gentoo.org/glsa/202105-20
- https://www.oracle.com/security-alerts/cpujan2022.html
JSON original (NVD)
Mostrar
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