This vulnerability (CVE-2025-59969) involves a classic buffer overflow (CWE-120) in the advanced forwarding toolkit (evo-aftmand/evo-pfemand) of Juniper Networks Junos OS Evolved on PTX and QFX5000 Series devices. It allows an unauthenticated attacker with adjacent network access to cause a Denial of Service by sending crafted multicast packets that trigger crashes and restarts of line cards or devices. The issue affects multiple versions before certain patched releases across Junos OS Evolved versions 22.2 through 24.4 on these platforms. The CVSS 3.1 vector indicates the attack requires adjacent network access, no privileges or user interaction, and impacts availability only. Juniper manages remediation for this cloud-hosted service, and patches are available in the specified fixed versions.

Successful exploitation results in a Denial of Service (DoS) condition by causing affected line cards or devices running the vulnerable components to crash and restart. The DoS can be sustained by continued receipt of crafted multicast packets. There is no impact on confidentiality or integrity according to the CVSS vector. The vulnerability affects network availability of Junos OS Evolved devices on PTX and QFX5000 Series platforms.

Patch is available in multiple fixed versions of Junos OS Evolved as listed in the advisory. Since this is a cloud-hosted service, Juniper Networks manages remediation server-side. Users should verify they are running a fixed version at or beyond the specified releases to mitigate this vulnerability. Patch status is confirmed as available. No additional mitigation steps are indicated by the vendor advisory.