CVE-2026-57020 (GCVE-0-2026-57020)

Vulnerability from cvelistv5 – Published: 2026-07-09 21:05 – Updated: 2026-07-09 21:05
VLAI
Title
Junos OS: QFX10000 Series: IPv6 multicast traffic received on non-IRB interfaces causes a multicast flood
Summary
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
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.1 (High)
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/AU:Y/R:U/RE:M
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
Impacted products
Vendor Product Version
Juniper Networks Junos OS Affected: 0 , < 23.2R2-S7 (custom)
Affected: 23.4 , < 23.4R2-S8 (custom)
Affected: 24.2 , < 24.2R2-S4 (custom)
Affected: 24.4 , < 24.4R2-S4 (custom)
Create a notification for this product.
Date Public
2026-07-08 16:00
Show details on NVD website
To clipboard 

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    "dateReserved": "2026-06-23T16:27:00.248Z",
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  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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