CVE-2025-21599

highpriority · track · 0EPSS 0.006 · 49 %ileDEEUNLRUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.60% (49th) EPSS

CVSS 7.5 · high

Is it mine?

18 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

8.7

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · sirt@juniper.net USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL

v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Lsecondary · ENISA EU

v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/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:X/R:X/V:X/RE:X/U:Xsecondary · sirt@juniper.net US

v4.06.6mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:U/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:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-401USCWE-401USCWE-401US

affected products (18)

Products and version ranges known to be affected.

Juniper JUNOSall versionscert_bundDEcpe:/o:juniper:junos:-
Juniper JUNOS Evolvedall versionscert_bundDEcpe:/o:juniper:junos:evolved
Juniper Networks Junos OS Evolved22.4-EVO → 22.4R3-S5-EVOenisa_euvdEU
Juniper Networks Junos OS Evolved23.2-EVO → 23.2R2-S2-EVOenisa_euvdEU
Juniper Networks Junos OS Evolved23.4-EVO → 23.4R2-S2-EVOenisa_euvdEU
Juniper Networks Junos OS Evolved24.2-EVO → 24.2R1-S2-EVO, 24.2R2-EVOenisa_euvdEU
Juniper Networks Inc. Junos OS Evolved22.4-EVO → 22.4R3-S5-EVOfstec_bduRU
Juniper Networks Inc. Junos OS Evolved23.2-EVO → 23.2R2-S2-EVOfstec_bduRU
Juniper Networks Inc. Junos OS Evolved23.4-EVO → 23.4R2-S2-EVOfstec_bduRU
Juniper Networks Inc. Junos OS Evolved24.2-EVO → 24.2R1-S2-EVOfstec_bduRU
Juniper Networks Inc. Junos OS Evolved24.2-EVO → 24.2R2-EVOfstec_bduRU
junosall versionsncsc_nlNLcpe:2.3:o:juniper:junos:-:*:*:*:*:*:*:*
junosall versionsncsc_nlNLcpe:2.3:o:juniper:junos:evolved:*:*:*:*:*:*:*
junos_os_evolvedall versionsncsc_nlNLcpe:2.3:a:juniper_networks:junos_os_evolved:*:*:*:*:*:*:*:*
juniper junos os evolved= 22.4nvdUScpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*
juniper junos os evolved= 23.2nvdUScpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*
juniper junos os evolved= 23.4nvdUScpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*
juniper junos os evolved= 24.2nvdUScpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

NCSC-2025-0006Kwetsbaarheden verholpen in Juniper JunOSNL2025-01-10csaf · ncsc_nlNL
Juniper heeft kwetsbaarheden verholpen in JunS (Specifiek voor JunOS en JunOS Evolved).
WID-SEC-W-2025-0031Juniper JUNOS: Mehrere Schwachstellen ermöglichen Denial of Service und InformationsoffenlegungDeutsch2025-01-08csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service Angriff durchzuführen und um vertrauliche Informationen preiszugeben.

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund ncsc_nl nvd NVD CVE.org MITRE

published 2025-01-09modified 2026-06-17

references (4)

External citations — patches, advisories, analysis.

scry

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