SB2026070851 - Improper handling of undefined parameters in Junos OS

Security Bulletin ID SB2026070851

CSH Severity

Medium

Patch available

YES

Number of vulnerabilities 1

Exploitation vector Remote access

Highest impact Denial of service

Breakdown by Severity

Low
Medium
High
Critical

Description

This security bulletin contains information about 1 vulnerability.

1) Improper handling of undefined parameters (CVE-ID: CVE-2026-57032)

CWE-ID: CWE-236 - Improper Handling of Undefined Parameters

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper handling of undefined parameters error in the packet forwarding engine (pfe). A remote user can 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.

Remediation

Install update from vendor's website.

References

https://supportportal.juniper.net/s/article/2026-07-Security-Bulletin-Junos-OS-EX-Series-Subscribing-to-an-unsupported-telemetry-sensor-path-causes-fxpc-process-crash-CVE-2026-57032