NVD

CVE-2026-57020 Detail

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.

Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.

CVSS 4.0 Severity and Vector Strings:

NIST: NVD

N/A

NVD assessment not yet provided.

Nist CVSS score does not match with CNA score

CNA: Juniper Networks, Inc.

CVSS-B 7.1 HIGH

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/AU:Y/R:U/RE:M

CVSS 3.x Severity and Vector Strings:

CNA: Juniper Networks, Inc.

Base Score: 6.5 MEDIUM

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS 2.0 Severity and Vector Strings:

National Institute of Standards and Technology

NIST: NVD

Base Score: N/A

NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL	Source(s)	Tag(s)
https://supportportal.juniper.net/JSA110080	Juniper Networks, Inc.	Vendor Advisory

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-754	Improper Check for Unusual or Exceptional Conditions	Juniper Networks, Inc.

Known Affected Software Configurations Switch to CPE 2.2

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Change History

3 change records found show changes

Initial Analysis by NIST 7/13/2026 4:57:06 PM

Action

Type

Old Value

New Value

Added

CPE Configuration

Record truncated, showing 2048 of 2430 characters.
View Entire Change Record

AND
     OR
          *cpe:2.3:o:juniper:junos:23.2:r1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r1-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r1-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:-:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:-:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r1-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:-:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r1-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s3:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r1-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2-s3:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2-s4:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s4:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r1-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:-:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r1-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r1-s3:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r2-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s5:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r2-s2:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r2-s1:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.2:r2-s5:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:23.4:r2-s6:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.2:r2-s3:*:*:*:*:*:*
          *cpe:2.3:o:juniper:junos:24.4:r2-s2:

Added

Reference Type

Juniper Networks, Inc.: https://supportportal.juniper.net/JSA110080 Types: Vendor Advisory

New CVE Received from Juniper Networks, Inc. 7/09/2026 6:17:06 PM

Action	Type	New Value
Added	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.
Added	CVSS V4.0	AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X
Added	CVSS V3.1	AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Added	CWE	CWE-754
Added	Reference	https://supportportal.juniper.net/JSA110080
Added	Affected	[{"vendor":"Juniper Networks","product":"Junos OS","defaultStatus":"unaffected","platforms":["QFX10000 Series"],"versions":[{"version":"0","lessThan":"23.2R2-S7","versionType":"custom","status":"affected"},{"version":"23.4","lessThan":"23.4R2-S8","versionType":"custom","status":"affected"},{"version":"24.2","lessThan":"24.2R2-S4","versionType":"custom","status":"affected"},{"version":"24.4","lessThan":"24.4R2-S4","versionType":"custom","status":"affected"}]}]

Quick Info

CVE Dictionary Entry:
CVE-2026-57020
NVD Published Date:
07/09/2026
NVD Last Modified:
07/13/2026
Source:
Juniper Networks, Inc.

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