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.
Published: 2026-07-09
Updated: 2026-07-13
Base Score: 6.1
Vector: CVSS2#AV:A/AC:L/Au:N/C:N/I:N/A:C
Severity: Medium
Base Score: 6.5
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: Medium
Base Score: 7.1
Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L
Severity: High
EPSS: 0.00269