An Incorrect Synchronization vulnerability in the management daemon (mgd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-based attacker with low privileges to cause a complete Denial-of-Service (DoS) of the management plane.
When NETCONF sessions are quickly established and disconnected, a locking issue causes mgd processes to hang in an unusable state. When the maximum number of mgd processes has been reached, no new logins are possible. This leads to the inability to manage the device and requires a power-cycle to recover.
This issue can be monitored by checking for mgd processes in lockf state in the output of 'show system processes extensive':
user@host> show system processes extensive | match mgd
<pid> root 20 0 501M 4640K lockf 1 0:01 0.00% mgd
If the system still can be accessed (either via the CLI or as root, which might still be possible as last resort as this won't invoke mgd), mgd processes in this state can be killed with 'request system process terminate <PID>' from the CLI or with 'kill -9 <PID>' from the shell.
This issue affects:
Junos OS:
* 23.4 versions before 23.4R2-S4,
* 24.2 versions before 24.2R2-S1,
* 24.4 versions before 24.4R1-S3, 24.4R2;
This issue does not affect Junos OS versions before 23.4R1;
Junos OS Evolved:
* 23.4 versions before 23.4R2-S5-EVO,
* 24.2 versions before 24.2R2-S1-EVO,
* 24.4 versions before 24.4R1-S3-EVO, 24.4R2-EVO.
This issue does not affect Junos OS Evolved versions before 23.4R1-EVO;
CVSS Score
7.1
EPSS Score
0.0
Published
2026-04-09
An Incorrect Initialization of Resource vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series and QFX Series device allows an unauthenticated, network-based attacker to cause an integrity impact to downstream networks.
When the same family inet or inet6 filter is applied on an IRB interface and on a physical interface as egress filter on EX4100, EX4400, EX4650 and QFX5120 devices, only one of the two filters will be applied, which can lead to traffic being sent out one of these interfaces which should have been blocked.
This issue affects Junos OS on EX Series and QFX Series:
* 23.4 version 23.4R2-S6,
* 24.2 version 24.2R2-S3.
No other Junos OS versions are affected.
CVSS Score
6.9
EPSS Score
0.0
Published
2026-04-09
A UNIX Symbolic Link (Symlink) Following vulnerability in the CLI of Juniper Networks Junos OS allows a local, authenticated attacker with low privileges to escalate their privileges to root which will lead to a complete compromise of the system.
When after a user has performed a specific 'file link ...' CLI operation, another user commits (unrelated configuration changes), the first user can login as root.
This issue affects Junos OS:
* all versions before 23.2R2-S7,
* 23.4 versions before 23.4R2-S6,
* 24.2 versions before 24.2R2-S3,
* 24.4 versions before 24.4R2-S2,
* 25.2 versions before 25.2R2.
This issue does not affect versions 25.4R1 or later.
CVSS Score
7.0
EPSS Score
0.0
Published
2026-04-09
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
8.7
EPSS Score
0.0
Published
2026-01-15
An Unchecked Return Value vulnerability in the DNS module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
If an SRX Series device configured for DNS processing, receives a specifically formatted DNS request flowd will crash and restart, which causes a service interruption until the process has recovered.
This issue affects Junos OS on SRX Series:
* 23.4 versions before 23.4R2-S5,
* 24.2 versions before 24.2R2-S1,
* 24.4 versions before 24.4R2.
This issue does not affect Junos OS versions before 23.4R1.
CVSS Score
8.7
EPSS Score
0.0
Published
2026-01-15
A Use After Free vulnerability in the chassis daemon (chassisd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-based attacker authenticated with low privileges to cause a Denial-of-Service (DoS).
When telemetry collectors are frequently subscribing and unsubscribing to sensors continuously over a long period of time, telemetry-capable processes like chassisd, rpd or mib2d will crash and restart, which - depending on the process - can cause a complete outage until the system has recovered.
This issue affects:
Junos OS:
* all versions before 22.4R3-S8,
* 23.2 versions before 23.2R2-S5,
* 23.4 versions before 23.4R2;
Junos OS Evolved:
* all versions before 22.4R3-S8-EVO,
* 23.2 versions before 23.2R2-S5-EVO,
* 23.4 versions before 23.4R2-EVO.
CVSS Score
7.1
EPSS Score
0.0
Published
2026-01-15
A Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in the method to collect FPC Ethernet firmware statistics of Juniper Networks Junos OS on MX10k Series allows a local, low-privileged attacker executing the 'show system firmware' CLI command to cause an LC480 or LC2101 line card to reset.
On MX10k Series systems with LC480 or LC2101 line cards, repeated execution of the 'show system firmware' CLI command can cause the line card to crash and restart. Additionally, some time after the line card crashes, chassisd may also crash and restart, generating a core dump.This issue affects Junos OS on MX10k Series:
* all versions before 21.2R3-S10,
* from 21.4 before 21.4R3-S9,
* from 22.2 before 22.2R3-S7,
* from 22.4 before 22.4R3-S6,
* from 23.2 before 23.2R2-S2,
* from 23.4 before 23.4R2-S3,
* from 24.2 before 24.2R2.
CVSS Score
6.8
EPSS Score
0.0
Published
2026-01-15
An Improper Locking vulnerability in the GTP plugin of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos).
If an SRX Series device receives a specifically malformed GPRS Tunnelling Protocol (GTP) Modify Bearer Request message, a lock is acquired and never released. This results in other threads not being able to acquire a lock themselves, causing a watchdog timeout leading to FPC crash and restart. This issue leads to a complete traffic outage until the device has automatically recovered.
This issue affects Junos OS on SRX 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-S3,
* 24.4 versions before 24.4R2-S2,
* 25.2 versions before 25.2R1-S1, 25.2R2.
CVSS Score
8.7
EPSS Score
0.0
Published
2026-01-15
An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).
If an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart.
This issue affects Junos OS on SRX Series:
* 23.2 versions from 23.2R2-S2 before 23.2R2-S5,
* 23.4 versions from 23.4R2-S1 before 23.4R2-S5,
* 24.2 versions before 24.2R2-S2,
* 24.4 versions before 24.4R1-S3, 24.4R2.
Earlier versions of Junos are also affected, but no fix is available.
CVSS Score
8.7
EPSS Score
0.0
Published
2026-01-15
An Improper Handling of Exceptional Conditions vulnerability in the packet forwarding engine (PFE) of Juniper Networks Junos OS on SRX Series allows an unauthenticated network-based attacker sending a specific ICMP packet through a GRE tunnel to cause the PFE to crash and restart.
When PowerMode IPsec (PMI) and GRE performance acceleration are enabled and the device receives a specific ICMP packet, a crash occurs in the SRX PFE, resulting in traffic loss. PMI is enabled by default, and GRE performance acceleration can be enabled by running the configuration command shown below. PMI is a mode of operation that provides IPsec performance improvements using Vector Packet Processing.
Note that PMI with GRE performance acceleration is only supported on specific SRX platforms.
This issue affects Junos OS on the SRX Series:
* all versions before 21.4R3-S12,
* from 22.4 before 22.4R3-S8,
* from 23.2 before 23.2R2-S5,
* from 23.4 before 23.4R2-S5,
* 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
8.7
EPSS Score
0.0
Published
2026-01-15