Cyber Posture

CVE-2025-21599

High

Published: 09 January 2025

Published
09 January 2025
Modified
26 January 2026
KEV Added
Patch
CVSS Score 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0034 56.8th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Description

A Missing Release of Memory after Effective Lifetime vulnerability in the Juniper Tunnel Driver (jtd) of Juniper Networks Junos OS Evolved allows an unauthenticated network-based attacker to cause Denial of Service.  Receipt of specifically malformed IPv6 packets, destined to the device, causes kernel memory to not be freed, resulting in memory exhaustion leading to a system crash and Denial of Service (DoS). Continuous receipt and processing of these packets will continue to exhaust kernel memory, creating a sustained Denial of Service (DoS) condition. This issue only affects systems configured with IPv6. This issue affects Junos OS Evolved:  * from 22.4-EVO before 22.4R3-S5-EVO,  * from 23.2-EVO before 23.2R2-S2-EVO,  * from 23.4-EVO before 23.4R2-S2-EVO,  * from 24.2-EVO before 24.2R1-S2-EVO, 24.2R2-EVO. This issue does not affect Juniper Networks Junos OS Evolved versions prior to 22.4R1-EVO.

Security Summary

CVE-2025-21599 is a Missing Release of Memory after Effective Lifetime vulnerability (CWE-401) in the Juniper Tunnel Driver (jtd) component of Juniper Networks Junos OS Evolved. It affects systems configured with IPv6 support running versions from 22.4-EVO before 22.4R3-S5-EVO, 23.2-EVO before 23.2R2-S2-EVO, 23.4-EVO before 23.4R2-S2-EVO, 24.2-EVO before 24.2R1-S2-EVO and 24.2R2-EVO. Versions of Junos OS Evolved prior to 22.4R1-EVO are not affected. The vulnerability has a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

An unauthenticated network-based attacker can exploit this vulnerability by sending specifically malformed IPv6 packets destined to the device. Receipt and processing of these packets prevents kernel memory from being freed after its effective lifetime, resulting in progressive memory exhaustion. This leads to a system crash and Denial of Service (DoS), with continuous packet transmission sustaining the DoS condition.

Mitigation details, including available patches and precise affected configurations, are provided in the Juniper Networks security advisory JSA92869 at https://supportportal.juniper.net/JSA92869.

Details

CWE(s)
CWE-401

Affected Products

juniper
junos os evolved
22.4, 23.2, 23.4, 24.2

References