CVE-2026-21903

6.5 MEDIUM
Published: January 15, 2026 Modified: January 23, 2026
View on NVD

Description

A Stack-based Buffer Overflow vulnerability in the Packet Forwarding Engine (pfe) of Juniper Networks Junos OS allows a network-based attacker, authenticated with low privileges to cause a Denial-of-Service (DoS). Subscribing to telemetry sensors at scale causes all FPC connections to drop, resulting in an FPC crash and restart. The issue was not seen when YANG packages for the specific sensors were installed. This issue affects Junos OS:  * all versions before 22.4R3-S7, * 23.2 version before 23.2R2-S4, * 23.4 versions before 23.4R2.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://kb.juniper.net/JSA106022
Source: sirt@juniper.net
Vendor Advisory
https://supportportal.juniper.net/JSA106022
Source: sirt@juniper.net
Vendor Advisory

2 reference(s) from NVD

Quick Stats

CVSS v3 Score
6.5 / 10.0
EPSS (Exploit Probability)
0.0%
3th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

juniper