SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

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 8.7EPSS 0.42%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.42% probability · 35th percentile
CISA KEV
Not listed
Weakness
CWE-754
Affected
juniper/junos
Source
sirt@juniper.net

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.