CVE-2025-21595
published 2025-04-09CVE-2025-21595: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evolved…
PriorityP430medium6.5CVSS 3.1
AVAACLPRNUINSUCNINAH
EPSS
0.25%
15.8th percentile
A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause an FPC to crash, leading to Denial of Service (DoS).
On all Junos OS and Junos OS Evolved platforms, in an EVPN-VXLAN scenario, when specific ARP packets are received on an IPv4 network, or specific NDP packets are received on an IPv6 network, kernel heap memory leaks, which eventually leads to an FPC crash and restart.
This issue does not affect MX Series platforms.
Heap size growth on FPC can be seen using below command.
user@host> show chassis fpc
Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%)
Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Buffer
0 Online 45 3 0 2 2 2 32768 19 0 <<<<<<< Heap increase in all fPCs
This issue affects Junos OS:
* All versions before 21.2R3-S7,
* 21.4 versions before 21.4R3-S4,
* 22.2 versions before 22.2R3-S1,
* 22.3 versions before 22.3R3-S1,
* 22.4 versions before 22.4R2-S2, 22.4R3.
and Junos OS Evolved:
* All versions before 21.2R3-S7-EVO,
* 21.4-EVO versions before 21.4R3-S4-EVO,
* 22.2-EVO versions before 22.2R3-S1-EVO,
* 22.3-EVO versions before 22.3R3-S1-EVO,
* 22.4-EVO versions before 22.4R3-EVO.
Affected
24 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| juniper | junos | < 21.2 | 21.2 |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos | — | — |
| juniper | junos_os | — | — |
| juniper | junos_os_evolved | < 21.2 | 21.2 |
| juniper | junos_os_evolved | — | — |
| juniper | junos_os_evolved | — | — |
| juniper | junos_os_evolved | — | — |
| juniper | junos_os_evolved | — | — |
| juniper | junos_os_evolved | — | — |
| juniper | mx_series | — | — |
| juniper_networks | junos_os | < 21.2R3-S7 | 21.2R3-S7 |
| juniper_networks | junos_os | >= 21.4 < 21.4R3-S4 | 21.4R3-S4 |
| juniper_networks | junos_os | >= 22.2 < 22.2R3-S1 | 22.2R3-S1 |
| juniper_networks | junos_os | >= 22.3 < 22.3R3-S1 | 22.3R3-S1 |
| juniper_networks | junos_os | >= 22.4 < 22.4R2-S2, 22.4R3 | 22.4R2-S2, 22.4R3 |
| juniper_networks | junos_os_evolved | < 21.2R3-S7-EVO | 21.2R3-S7-EVO |
| juniper_networks | junos_os_evolved | >= 21.4-EVO < 21.4R3-S4-EVO | 21.4R3-S4-EVO |
| juniper_networks | junos_os_evolved | >= 22.2-EVO < 22.2R3-S1-EVO | 22.2R3-S1-EVO |
| juniper_networks | junos_os_evolved | >= 22.3-EVO < 22.3R3-S1-EVO | 22.3R3-S1-EVO |
| juniper_networks | junos_os_evolved | >= 22.4-EVO < 22.4R3-EVO | 22.4R3-EVO |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.07.1HIGHCVSS:4.0/AV:A/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:X/R:X/V:X/RE:X/U:X
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GHSA
GHSA-7fvw-hrgg-4cr6: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evo
ghsa_unreviewed·2025-04-09
CVE-2025-21595 [HIGH] CWE-401 GHSA-7fvw-hrgg-4cr6: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evo
A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause an FPC to crash, leading to Denial of Service (DoS).
On all Junos OS and Junos OS Evolved platforms, in an EVPN-VXLAN scenario, when specific ARP packets are received on an IPv4 network, or specific NDP packets are received on an IPv6 network, kernel heap memory leaks, which eventually leads to an FPC crash and restart.
This issue does not affect MX Series platforms.
Heap size growth on FPC can be seen using below command.
user@host> show chassis fpc
Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%)
Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Bu
Juniper
CVE-2025-21595: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evo
vendor_juniper·2025-04-09·CVSS 6.5
CVE-2025-21595 [MEDIUM] CWE-401 CVE-2025-21595: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evo
CVE-2025-21595: A Missing Release of Memory after Effective Lifetime vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause an FPC to crash, leading to Denial of Service (DoS).
On all Junos OS and Junos OS Evolved platforms, in an EVPN-VXLAN scenario, when specific ARP packets are received on an IPv4 network, or specific NDP packets are received on an IPv6 network, kernel heap memory leaks, which eventually leads to an FPC crash and restart.
This issue does not affect MX Series platforms.
Heap size growth on FPC can be seen using below command.
user@host> show chassis fpc
Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%)
Slot State (C) Total Interrupt 1min 5min 15min D
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-04-09
Published