CVE-2026-101943: Junos OS and Junos OS Evolved: An attacker causes rpd crash and denial of service when EVPN is configured

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-14 · updated 2026-10-18
Weakness: CWE-20

Description

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.

Affected products

Juniper Junos OS: before 23.2R2-S7.7; from 23.4 before 23.4R2-S8.13; from 24.2 before 24.2R2-S5.5; from 24.4 before 24.4R2-S5; from 25.2 before 25.2R2-S2; from 25.4 before 25.4R1-S3 — fixed in 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3
Juniper Networks Junos OS Evolved: before 23.2R2-S7.7-EVO; from 23.4 before 23.4R2-S8.11-EVO; from 24.2 before 24.2R2-S5.6-EVO; from 24.4 before 24.4R2-S5-EVO; from 25.2 before 25.2R2-S2-EVO; from 25.4 before 25.4R1-S3-EVO — fixed in 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

How to fix

Upgrade to a fixed version: Juniper Junos OS 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5; Juniper Networks Junos OS Evolved 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO. Check the vendor advisory for mitigations.

References

https://supportportal.juniper.net/JSA112187

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