Junos OS: MX Series: In DS-lite and NAT scenario receipt of crafted IPv6 traffic causes port block (Juniper Networks Junos OS)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.42 % · percentile 37 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- juniper
- NVD status
- Analyzed
Description
An Improper Check for Unusual or Exceptional Conditions vulnerability in the pfe (packet forwarding engine) of Juniper Networks Junos OS on MX Series causes a port within a pool to be blocked leading to Denial of Service (DoS). In a DS-Lite (Dual-Stack Lite) and NAT (Network Address Translation) scenario, when crafted IPv6 traffic is received and prefix-length is set to 56, the ports assigned to the user will not be freed. Eventually, users cannot establish new connections. Affected FPC/PIC need to be manually restarted to recover. Following is the command to identify the issue: user@host> show services nat source port-block Host_IP External_IP Port_Block Ports_Used/ Block_State/ Range Ports_Total Left_Time(s) 2001:: x.x.x.x 58880-59391 256/256*1 Active/- >>>>>>>>port still usedThis issue affects Junos OS on MX Series: * from 21.2 before 21.2R3-S8, * from 21.4 before 21.4R3-S7, * from 22.1 before 22.1R3-S6, * from 22.2 before 22.2R3-S4, * from 22.3 before 22.3R3-S3, * from 22.4 before 22.4R3-S2, * from 23.2 before 23.2R2-S1, * from 23.4 before 23.4R1-S2, 23.4R2. This issue does not affect versions before 20.2R1.
Weaknesses (CWE)
- CWE-754 — Improper Check for Unusual or Exceptional Conditions
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | juniper |
| CVSS 4.0 | HIGH 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:U | juniper |
| CVSS 4.0 | HIGH 8.7 | CVSS: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:U/V:X/RE:X/U:X | NVD · sirt@juniper.net (Secondary) |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · sirt@juniper.net (Secondary) |
European references
- ENISA EUVD · EUVD-2025-10531
- GCVE · GCVE-0-2025-21594
CERT-FR advisories
- CERTFR-2025-AVI-0304 — Multiples vulnérabilités dans les produits Juniper Networks · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:juniper:junos:21.2:-:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r1-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r1-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r2-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r2-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s3:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s4:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s5:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s6:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.2:r3-s7:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:-:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r1-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r1-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r2-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r2-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s3:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s4:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s5:*:*:*:*:*:*cpe:2.3:o:juniper:junos:21.4:r3-s6:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:-:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r1-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r1-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r2-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r2-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r3:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r3-s1:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r3-s2:*:*:*:*:*:*cpe:2.3:o:juniper:junos:22.1:r3-s3:*:*:*:*:*:*- +41 more
Affected products
| Product | Versions |
|---|---|
| Juniper Networks · Junos OS | affected 0 < 21.2R3-S8 ; affected 21.4 < 21.4R3-S7 ; affected 22.1 < 22.1R3-S6 ; affected 22.2 < 22.2R3-S4 ; affected 22.3 < 22.3R3-S3 ; affected 22.4 < 22.4R3-S2 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |