Juniper Junos OS: Denial of service in routing daemon rpd via BGP EVPN update
Summary
An Improper Input Validation vulnerability in the routing protocol daemon (rpd) of Junos OS and Junos OS Evolved allows an unauthenticated, network-based attacker to crash rpd with a crafted BGP EVPN update message, causing a denial of service. The flaw only matters where EVPN is configured. Because BGP carries routing for wider networks, a restart can disrupt connectivity beyond the affected device. The CVSS v4.0 base score is 8.7 (High). Juniper SIRT is not aware of any malicious exploitation.
Affected
- Junos OS: releases before 23.2R2-S7.7; 23.4 before 23.4R2-S8.13; 24.2 before 24.2R2-S5.5; 24.4 before 24.4R2-S5; 25.2 before 25.2R2-S2; 25.4 before 25.4R1-S3; 26.2 before 26.2R1-S2 (default configuration is unaffected)
- Junos OS Evolved: releases before 23.2R2-S7.7-EVO; 23.4 before 23.4R2-S8.11-EVO; 24.2 before 24.2R2-S5.6-EVO; 24.4 before 24.4R2-S5-EVO; 25.2 before 25.2R2-S2-EVO; 25.4 before 25.4R1-S3-EVO; 26.2 before 26.2R1-S2-EVO; 23.4X100; 25.2X100 before 25.2X100-D35-EVO; 25.4X300 before 25.4X300-D40-EVO (default configuration is unaffected)
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
- Releases 23.2, 23.4 and 24.2 (and their Evolved equivalents) have been respun; previously published builds have been rebuilt.
Workaround
Unknown. Juniper lists no known workarounds for this issue.
Exploitation
- Juniper SIRT is not aware of any malicious exploitation.
- CISA SSVC: exploitation none, automatable yes, technical impact partial.
Our recommendation
- Check whether any Juniper device runs BGP EVPN, and record the Junos or Junos OS Evolved version with show version.
- Compare the version with Juniper advisory JSA112187 and schedule the update to a fixed release.
- Review BGP peer authentication and filters for EVPN peers, especially those outside your control.
- Monitor for rpd restarts and crash files.
- If you depend on an ISP or MSP for BGP services, ask whether their Juniper edge is patched.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- Juniper Security Advisory JSA112187 supportportal.juniper.net
- VulDB entry for the vulnerability vuldb.com
- Strix AI CVE summary www.strix.ai
- ThreatInt CVE summary cve.threatint.com
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, 03:55.
Original description (NVD)
An Improper Input Validation vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated network-based attacker to cause a denial of service via a crafted BGP EVPN update message.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
Affected? We can help.
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