Junos OS: EX Series: Subscribing to an unsupported telemetry sensor path causes fxpc process crash

published 2026-07-09 4 mo ago modified 2026-10-25 15 d ago also EUVD-2026-42723

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 36%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

Juniper Networks Junos OS 23.2R2-S7, 23.4R2-S8, 24.2R2-S5, 24.4R2

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 4 mo ago (2026-07-10)

Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M
CNA	4.0	7.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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:A/V:X/RE:M/U:X

Affected products

Juniper Networks Junos OS

Classification

Weakness

CWE-236 Improper Handling of Undefined Parameters

References

supportportal.juniper.net /JSA110092
vendor-advisory, mitigation

Sources

CVE List CVE-2026-57032
NVD CVE-2026-57032

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary