CVE-2026-57020
Full vulnerability record from the local CVENow database.
Description
An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on QFX10000 Series allows an unauthenticated, adjacent attacker to cause a Denial-of-Service (DoS). On all QFX10000 platforms in an EVPN-VxLAN scenario, if an attacker sends IPv6 multicast traffic and these packets reach the non-IRB interface of a spine switch it floods the packet to other spines and all Ethernet Segment Identifier (ESI) leaf switches. This flooding causes the packet to be forwarded in a endless loop, which can lead to saturation of the involved links and in turn impact to legitimate traffic. This issue affects Junos OS on QFX10000 Series: * all versions before 23.2R2-S7, * 23.4 versions before 23.4R2-S8, * 24.2 versions before 24.2R2-S4, * 24.4 versions before 24.4R2-S4. This issue does not affect Junos version after 24.4 as the QFX10000 Series devices are not supported on newer versions anymore.
Severity
HIGH
CVSS score
7.1
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-09 22:17:06.887000
Last modified
2026-10-25 15:10:00.147000
View original CVE JSON
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"sourceIdentifier": "[email protected]",
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"value": "An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on QFX10000 Series allows an unauthenticated, adjacent attacker to cause a Denial-of-Service (DoS).\n\nOn all QFX10000 platforms in an EVPN-VxLAN scenario, if an attacker sends IPv6 multicast traffic and these packets reach the non-IRB interface of a spine switch it floods the packet to other spines and all Ethernet Segment Identifier (ESI) leaf switches. This flooding causes the packet to be forwarded in a endless loop, which can lead to saturation of the involved links and in turn impact to legitimate traffic.\n\n\n\nThis issue affects Junos OS on QFX10000 Series:\n\n\n * all versions before 23.2R2-S7,\n * 23.4 versions before 23.4R2-S8,\n * 24.2 versions before 24.2R2-S4,\n * 24.4 versions before 24.4R2-S4.\n\n\n\nThis issue does not affect Junos version after 24.4 as the QFX10000 Series devices are not supported on newer versions anymore."
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"value": "Una vulnerabilidad de Comprobación Incorrecta de Condiciones Inusuales o Excepcionales en el motor de reenvío de paquetes (pfe) de Juniper Networks Junos OS en la serie QFX10000 permite a un atacante adyacente no autenticado causar una Denegación de Servicio (DoS).\n\nEn todas las plataformas QFX10000 en un escenario EVPN-VxLAN, si un atacante envía tráfico multicast IPv6 y estos paquetes alcanzan la interfaz no-IRB de un switch spine, inunda el paquete a otros spines y a todos los switches leaf de Identificador de Segmento Ethernet (ESI). Esta inundación provoca que el paquete sea reenviado en un bucle sin fin, lo que puede llevar a la saturación de los enlaces involucrados y, a su vez, a un impacto en el tráfico legítimo.\n\nEste problema afecta a Junos OS en la serie QFX10000:\n\n* todas las versiones anteriores a 23.2R2-S7,\n* versiones 23.4 anteriores a 23.4R2-S8,\n* versiones 24.2 anteriores a 24.2R2-S4,\n* versiones 24.4 anteriores a 24.4R2-S4.\n\nEste problema no afecta a las versiones de Junos posteriores a 24.4, ya que los dispositivos de la serie QFX10000 ya no son compatibles con versiones más recientes."
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