A malicious neighbor using the Label Distribution Protocol (LDP) can send a malformed Label Mapping message that overflows a stack buffer in the device’s routing protocol daemon (rpd). This vulnerability allows the attacker to crash the process or execute arbitrary code with the privileges of the routing engine, potentially giving full control over the router’s operating system. The overflow is a classic buffer overflow flaw, tagged as CWE‑121.

Juniper Networks Junos OS and Junos OS Evolved devices running the affected releases listed in the advisory. Fixed releases start with Junos OS 23.2R2‑S7.7 and later, and Junos OS Evolved 23.2R2‑S7.7‑EVO and later, including all subsequent releases.

With a CVSS score of 8.7, the vulnerability is high severity. The EPSS metric is not available, and the flaw is not reported in the CISA KEV catalog. The likely attack vector involves an unauthenticated adjacent LDP peer that can be located on the same network segment or a routed path to the target device. No known workarounds exist, so the risk remains significant until the firmware is updated or LDP is removed from the configuration.