Junos OS (SRX firewalls)
CVE-2026-57032: EX Series: Subscribing to an unsupported telemetry sensor path causes fxpc process crash
An Improper Handling of Undefined Parameters vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on EX Series devices allows an authenticated attacker with low privileges to cause a Denial-of-Service (DoS).
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Junos OS (EX3400, EX4100, EX4400, EX2300, EX4000) 0 | 23.2R2-S7 or later |
| Junos OS (EX3400, EX4100, EX4400, EX2300, EX4000) 23.4 | 23.4R2-S8 or later |
| Junos OS (EX3400, EX4100, EX4400, EX2300, EX4000) 24.2 | 24.2R2-S5 or later |
| Junos OS (EX3400, EX4100, EX4400, EX2300, EX4000) 24.4 | 24.4R2 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
An Improper Handling of Undefined Parameters vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on EX Series devices allows an authenticated attacker with low privileges to cause a Denial-of-Service (DoS).
If an attempt is made to subscribe to an unsupported telemetry sensor path on EX2300, EX3400, EX4000, EX4100 and EX4400 via gRPC, this causes the FPC to crash. This leads to a complete service outage until the module has automatically restarted.
The following log message can be seen when this issue happens:
agentd[<PID>]: AGENTD_RESOURCE_NOT_FOUND: No resource name found for <sensor>
This issue affects Junos OS on
EX2300, EX3400, EX4000, EX4100 and EX4400
devices:
- all versions before 23.2R2-S7,
- 23.4 versions before 23.4R2-S8,
- 24.2 versions before 24.2R2-S5,
- 24.4 versions before 24.4R2.
Am I affected?
To be exposed to this issue gRPC needs to be enabled via at least one of:
[ system services http servers ] [ system services extension-service request-response grpc ]
Workarounds
There are no known workarounds for this issue. To reduce the risk of exploitation use access lists or firewall filters to limit access to the device only from trusted hosts and administrators.
Exploitation
Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.