Junos OS (SRX firewalls)
CVE-2026-101999: An attacker causes rpd to crash when LDP is enabled
A Reachable Assertion vulnerability in the rpd process of Juniper Networks Junos OS and Junos EVO allows an adjacent attacker to cause a denial of service via an established LDP session carrying an IPv6 Prefix FEC in a specific Label message.
Published Juniper Networks advisory JSA112187
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Junos OS 0 | 23.2R2-S7.7 or later |
| Junos OS 23.4 | 23.4R2-S8.13 or later |
| Junos OS 24.2 | 24.2R2-S5.5 or later |
| Junos OS 24.4 | 24.4R2-S5 or later |
| Junos OS 25.2 | 25.2R2-S2 or later |
| Junos OS 25.4 | 25.4R1-S3 or later |
| Junos OS 26.2 | 26.2R1-S2 or later |
| Junos OS Evolved 0 | 23.2R2-S7.7-EVO or later |
| Junos OS Evolved 23.4 | 23.4R2-S8.11-EVO or later |
| Junos OS Evolved 24.2 | 24.2R2-S5.6-EVO or later |
| Junos OS Evolved 24.4 | 24.4R2-S5-EVO or later |
| Junos OS Evolved 25.2 | 25.2R2-S2-EVO or later |
| Junos OS Evolved 25.4 | 25.4R1-S3-EVO or later |
| Junos OS Evolved 26.2 | 26.2R1-S2-EVO or later |
| Junos OS Evolved 23.4X100 | See the advisory |
| Junos OS Evolved 25.2X100 | 25.2X100-D35-EVO or later |
| Junos OS Evolved 25.4X300 | 25.4X300-D40-EVO or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
In short
A reachable assertion flaw in the rpd process of Junos OS allows an attacker to trigger a denial of service. By establishing an LDP session and sending a specific Label message containing an IPv6 Prefix FEC, an attacker on an adjacent network can crash the service. This attack requires no user interaction or prior authentication.
Written by a language model from the vendor's description. Versions, fixes and exploitation status on this page come straight from the vendor and CISA.
The vendor's description
A Reachable Assertion vulnerability in the rpd process of Juniper Networks Junos OS and Junos EVO allows an adjacent attacker to cause a denial of service via an established LDP session carrying an IPv6 Prefix FEC in a specific Label message.
Am I affected?
[ protocols ldp interface <ifl> ]
Workarounds
There are no known workarounds for this issue.
Exploitation
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 19 Oct 2026.