High severity · published Jan 9, 2025
CVE-2025-21599
Junos OS Evolved: Receipt of specifically malformed IPv6 packets causes kernel memory exhaustion leading to Denial of Service
7.5
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
JO
Junos OS Evolved · Juniper Networks
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, 24.2R2-EVO · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-21599
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-21599
Vendor Advisory
https://supportportal.juniper.net/JSA92869
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