CVE-2025-30660
Junos OS: MX Series: Decapsulation of specific GRE packets leads to PFE reset
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Junos OS: MX Series: Decapsulation of specific GRE packets leads to PFE reset
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.
- Record
CVE-2025-30660- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/RE:M - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
EUVDEUVD-2025-10517
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.
- Record
EUVD-2025-10517- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/RE:M - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-332p-x9c3-3hm3
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding...
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.
- Record
GHSA-332p-x9c3-3hm3- CVSS 4.0
- 8.7 High
CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2025-30660- CVSS 4.0
- 8.7 High
CVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-30660 is a high vulnerability (CVSS 8.7) in Juniper Junos, published April 9, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.43%, the 37th percentile. No source names a fixed version.