CVE-2026-102020: CWE-617 Reachable Assertion in Juniper Networks Junos OS

This vulnerability (CVE-2026-102020) involves a reachable assertion failure in the rpd process of Juniper Networks Junos OS and Junos OS Evolved. The flaw can be triggered by an authenticated attacker sending crafted BGP-LS routing updates, leading to a denial of service condition. The vulnerability affects a range of Junos OS versions prior to certain fixed releases, including both standard and evolved variants. The CVSS 3.1 score of 7.5 reflects a network attack vector with low complexity and no privileges required, no user interaction, and impact limited to availability (denial of service). No known exploits are reported in the wild at this time.

Successful exploitation results in denial of service by crashing or disrupting the rpd process responsible for routing protocol operations. There is no impact on confidentiality or integrity. The disruption can affect network availability and routing stability on affected Junos OS devices.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official patch links are provided in the input data. Users should monitor Juniper Networks advisories for updates and apply patches or mitigations once available. Until then, restrict authenticated access to the routing protocol processes and monitor for unusual BGP-LS routing updates.