Junos OS: Denial of service via crafted BGP MVPN signaling update

Summary

Juniper Networks Junos OS and Junos OS Evolved contain a flaw in the rpd process (Routing Protocol Daemon). A configured BGP MVPN peer can send a crafted BGP MVPN signaling update that causes a denial of service and a routing outage. The attacker must already be a configured BGP MVPN peer, so the risk is limited to networks that use BGP MVPN with the affected configuration. The CNA rates the issue CVSS 4.0 8.7 (High).

Affected

• Junos OS: releases below 23.2R2-S7.7, 23.4 to below 23.4R2-S8.13, 24.2 to below 24.2R2-S5.5, 24.4 to below 24.4R2-S5, 25.2 to below 25.2R2-S2, 25.4 to below 25.4R1-S3, 26.2 to below 26.2R1-S2
• Junos OS Evolved: releases below 23.2R2-S7.7-EVO, 23.4 to below 23.4R2-S8.11-EVO, 24.2 to below 24.2R2-S5.6-EVO, 24.4 to below 24.4R2-S5-EVO, 25.2 to below 25.2R2-S2-EVO, 25.4 to below 25.4R1-S3-EVO, 26.2 to below 26.2R1-S2-EVO, plus listed 23.4X100, 25.2X100 and 25.4X300 builds
• Required configuration: routing-instances <name> protocols mvpn provider-tunnel inter-as ingress-replication
• Version details are taken from the CNA record reproduced by third parties; verify them in JSA112187.

Fixed in

• 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, 25.2X100-D35-EVO, 25.4R1-S3-EVO, 25.4R2-EVO, 25.4X300-D40-EVO, 26.2R1-S2-EVO, 26.2R2-EVO, 26.4R1-EVO and all subsequent releases
• Juniper has rebuilt previously published respins for 23.2, 23.4 and 24.2 releases.

Workaround

• The CNA record states that there are no known workarounds.
• A secondary summary suggests disabling BGP MVPN signaling or removing the problematic BGP peer as an interim measure. This is unverified; confirm it in JSA112187 before use.

Exploitation

• Juniper SIRT is not aware of any malicious exploitation.
• CISA SSVC data in the CNA record: exploitation none, automatable yes, technical impact partial.
• No public proof-of-concept was found in the research, but this does not prove that none exists.

Our recommendation

• Inventory all Junos OS and Junos OS Evolved devices and their versions.
• Check whether BGP MVPN is configured on any device. If not, the risk is low; patch in the normal cycle.
• If BGP MVPN is configured, plan the upgrade to the fixed release listed in JSA112187.
• Until patched, restrict BGP peering to trusted, known neighbours.
• Check whether CVE-2026-102030 in the same advisory also applies, and monitor JSA112187 and NVD for updates.

Public exploits iAttack code is publicly available (PoC on GitHub, Metasploit or Exploit-DB).

PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.

Research sources

• Juniper Security Advisory JSA112187 supportportal.juniper.net
• OpenCVE: CVE-2026-102016 app.opencve.io
• Strix AI: CVE-2026-102016 www.strix.ai
• Threatint: CVE-2026-102016 cve.threatint.com
• BDU FSTEC: BDU:2026-17892 vulners.com
• OpenCVE: CVE-2026-102030 (same advisory) app.opencve.io

Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 03:25.