CVE-2026-101951

Junos OS and Junos OS Evolved: A BGP peer causes an rpd crash if a malformed MCAST-TREE NLRI is received and readvertised

Published Oct 14, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
An Improper Validation of Consistency within Input vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-adjacent configured BGP peer to cause a denial of service by sending a specifically malformed BGP MCAST-TREE update and this NLRI is then attempted to be readvertised.

Remediation

Vendor Solution

The following software releases have been updated to resolve this specific issue: Junos OS: 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 25.4R2, 26.2R1-S2, 26.2R2, 26.4R1, and all subsequent releases. Junos OS Evolved: 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 25.4R2-EVO, 26.2R1-S2-EVO, 26.2R2-EVO, 26.4R1-EVO, and all subsequent releases. Note: For Junos OS releases 23.2, 23.4, and 24.2, and Junos OS Evolved releases 23.2-EVO, 23.4-EVO, and 24.2-EVO, specific respins have been referenced. Previously published versions of these releases have been rebuilt to resolve the security vulnerabilities identified in this advisory.


Vendor Workaround

There are no known workarounds for this issue.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Juniper Networks
Juniper Networks junos Os
Juniper Networks junos Os Evolved
Vendors & Products Juniper Networks
Juniper Networks junos Os
Juniper Networks junos Os Evolved
Type Values Removed Values Added
Description An Improper Validation of Consistency within Input vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-adjacent configured BGP peer to cause a denial of service by sending a specifically malformed BGP MCAST-TREE update and this NLRI is then attempted to be readvertised.
Title Junos OS and Junos OS Evolved: A BGP peer causes an rpd crash if a malformed MCAST-TREE NLRI is received and readvertised
Weaknesses CWE-1288
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
juniper
Published
Updated
Oct 14, 2026, 8:46 PM
Reserved
Sep 28, 2026, 4:28 PM
Status
Awaiting Analysis
Published
Oct 14, 2026, 5:17 PM
Modified
Oct 15, 2026, 4:23 PM