CVE-2025-30660

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS on MX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).When processing a high rate of specific GRE traffic destined to the device, the respective PFE will hang causing traffic forwarding to stop.

When this issue occurs the following logs can be observed:

<fpc #> MQSS(0): LI-3: Received a parcel with more than 512B accompanying data CHASSISD_FPC_ASIC_ERROR: ASIC Error detected <...>

This issue affects Junos OS:

* all versions before 21.2R3-S9, * 21.4 versions before 21.4R3-S8, * 22.2 versions before 22.2R3-S4, * 22.4 versions before 22.4R3-S5, * 23.2 versions before 23.2R2-S2, * 23.4 versions before 23.4R2.