A Double Free vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX and MX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). On all SRX and MX Series platforms, when during TCP session establishment a specific sequence of packets is encountered a double free happens. This causes flowd to crash and the respective FPC to restart.
This issue affects Junos OS on SRX and MX Series:
* all versions before 22.4R3-S7,
* 23.2 versions before 23.2R2-S3,
* 23.4 versions before 23.4R2-S4,
* 24.2 versions before 24.2R2.
CVSS Score
7.5
EPSS Score
0.0
Published
2026-01-15
A Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in the SIP application layer gateway (ALG) of Juniper Networks Junos OS on SRX Series and MX Series with MX-SPC3 or MS-MPC allows an unauthenticated network-based attacker sending specific SIP messages over TCP to crash the flow management process, leading to a Denial of Service (DoS).
On SRX Series, and MX Series with MX-SPC3 or MS-MPC service cards, receipt of multiple SIP messages causes the SIP headers to be parsed incorrectly, eventually causing a continuous loop and leading to a watchdog timer expiration, crashing the flowd process on SRX Series and MX Series with MX-SPC3, or mspmand process on MX Series with MS-MPC.
This issue only occurs over TCP. SIP messages sent over UDP cannot trigger this issue.
This issue affects Junos OS on SRX Series and MX Series with MX-SPC3 and MS-MPC:
* all versions before 21.2R3-S10,
* from 21.4 before 21.4R3-S12,
* from 22.4 before 22.4R3-S8,
* from 23.2 before 23.2R2-S5,
* from 23.4 before 23.4R2-S6,
* from 24.2 before 24.2R2-S3,
* from 24.4 before 24.4R2-S1,
* from 25.2 before 25.2R1-S1, 25.2R2.
CVSS Score
7.5
EPSS Score
0.0
Published
2026-01-15
A NULL Pointer Dereference vulnerability in the chassis daemon (chassisd) of Juniper Networks Junos OS on MX, SRX and EX Series allows a local attacker with low privileges to cause a Denial-of-Service (DoS).
When a user executes the 'show chassis' command with specifically crafted options, chassisd will crash and restart. Due to this all components but the Routing Engine (RE) in the chassis are reinitialized, which leads to a complete service outage, which the system automatically recovers from.
This issue affects:
Junos OS on MX, SRX and EX Series:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2-S6,
* 24.2 versions before 24.2R2-S2,
* 24.4 versions before 24.4R2.
CVSS Score
5.5
EPSS Score
0.0
Published
2026-01-15
A Buffer Copy without Checking Size of Input vulnerability in the
Session Initialization Protocol (SIP) ALG of Juniper Networks Junos OS on MX Series and SRX Series allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS).
When memory utilization is high, and specific SIP packets are received, flowd/mspmand crashes. While the system recovers automatically, the disruption can significantly impact service stability. Continuous receipt of these specific SIP packets, while high utilization is present, will cause a sustained DoS condition. The utilization is outside the attackers control, so they would not be able to deterministically exploit this.
This issue affects Junos OS on SRX Series and MX Series:
* All versions before 22.4R3-S7,
* from 23.2 before 23.2R2-S4,
* from 23.4 before 23.4R2-S5,
* from 24.2 before 24.2R2.
CVSS Score
5.9
EPSS Score
0.001
Published
2025-10-09
An Improper Resource Shutdown or Release vulnerability in the SIP ALG of Juniper Networks Junos OS on MX Series with MS-MPC allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
When an MX Series device with an MS-MPC is configured with two or more service sets which are both processing SIP calls, a specific sequence of call events will lead to a crash and restart of the MS-MPC.
This issue affects Junos OS:
* all versions before 21.2R3-S9,
* 21.4 versions from 21.4R1,
* 22.2 versions before 22.2R3-S6,
* 22.4 versions before 22.4R3-S6.
As the MS-MPC is EoL after Junos OS 22.4, later versions are not affected.
This issue does not affect MX-SPC3 or SRX Series devices.
CVSS Score
5.9
EPSS Score
0.0
Published
2025-07-11
An Out-of-bounds Write vulnerability in the connectivity fault management (CFM) daemon of Juniper Networks Junos OS on MX Series with MPC-BUILTIN, MPC1 through MPC9 line cards allows an unauthenticated adjacent attacker to send a malformed packet to the device, leading to an FPC crash and restart, resulting in a Denial of Service (DoS).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue affects Juniper Networks:
Junos OS:
* All versions before 22.2R3-S1,
* from 22.4 before 22.4R2.
This feature is not enabled by default.
CVSS Score
6.5
EPSS Score
0.0
Published
2025-07-11
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 Score
7.5
EPSS Score
0.001
Published
2025-04-09
An Improper Handling of Additional Special Element vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MS-MPC, MS-MIC and SPC3, and SRX Series, allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
If the SIP ALG processes specifically formatted SIP invites, a memory corruption will occur which will lead to a crash of the FPC processing these packets. Although the system will automatically recover with the restart of the FPC, subsequent SIP invites will cause the crash again and lead to a sustained DoS.
This issue affects Junos OS on MX Series and SRX Series:
* all versions before 21.2R3-S9,
* 21.4 versions before 21.4R3-S10,
* 22.2 versions before 22.2R3-S6,
* 22.4 versions before 22.4R3-S5,
* 23.2 versions before 23.2R2-S3,
* 23.4 versions before 23.4R2-S3,
* 24.2 versions before 24.2R1-S2, 24.2R2.
CVSS Score
7.5
EPSS Score
0.001
Published
2025-04-09
A Missing Release of Memory after Effective Lifetime vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on MX Series allows an unauthenticated adjacent attacker to cause a Denial-of-Service (DoS).
In a subscriber management scenario, login/logout activity triggers a memory leak, and the leaked memory gradually increments and eventually results in a crash.
user@host> show chassis fpc
Temp CPU Utilization (%) CPU Utilization (%) Memory Utilization (%)
Slot State (C) Total Interrupt 1min 5min 15min DRAM (MB) Heap Buffer
2 Online 36 10 0 9 8 9 32768 26 0
This issue affects Junos OS on MX Series:
* All versions before 21.2R3-S9
* from 21.4 before 21.4R3-S10
* from 22.2 before 22.2R3-S6
* from 22.4 before 22.4R3-S5
* from 23.2 before 23.2R2-S3
* from 23.4 before 23.4R2-S3
* from 24.2 before 24.2R2.
CVSS Score
6.5
EPSS Score
0.0
Published
2025-04-09
An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS).
In a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and prefix-length is set to 56, the ports assigned to the user will not be freed. Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover.
Following is the command to identify the issue:
user@host> show services nat source port-block
Host_IP External_IP Port_Block Ports_Used/ Block_State/
Range Ports_Total Left_Time(s)
2001:: x.x.x.x 58880-59391 256/256*1 Active/- >>>>>>>>port still usedThis issue affects Junos OS on MX Series:
* from 21.2 before 21.2R3-S8,
* from 21.4 before 21.4R3-S7,
* from 22.1 before 22.1R3-S6,
* from 22.2 before 22.2R3-S4,
* from 22.3 before 22.3R3-S3,
* from 22.4 before 22.4R3-S2,
* from 23.2 before 23.2R2-S1,
* from 23.4 before 23.4R1-S2, 23.4R2.
This issue does not affect versions before 20.2R1.
CVSS Score
7.5
EPSS Score
0.001
Published
2025-04-09
Page 1