CVE-2020-25686

Estado: ModificadaBaja (3.7)—

A flaw was found in dnsmasq before version 2.83. When receiving a query, dnsmasq does not check for an existing pending request for the same name and forwards a new request. By default, a maximum of 150 pending queries can be sent to upstream servers, so there can be at most 150 queries for the same name. This flaw allows an off-path attacker on the network to substantially reduce the number of attempts that it would have to perform to forge a reply and have it accepted by dnsmasq. This issue is mentioned in the "Birthday Attacks" section of RFC5452. If chained with CVE-2020-25684, the attack complexity of a successful attack is reduced. 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:U/C:N/I:L/A:N
Puntuación base: 3.7

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 4.87%
Percentil entre todas las CVEs puntuadas: 92
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)

Arista — EOS Debian — Debian Linux Fedoraproject — Fedora Thekelleys — Dnsmasq

CWE

CWE-358
CWE-290

Referencias

JSON original (NVD)

Mostrar

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