Junos OS: Receipt of a specifically malformed ICMP packet causes an FPC restart (Juniper Networks Junos OS)

CVE-2026-0203
HIGH 7.1

At a glance

Source
NVD
EPSS
EPSS 0.26 % · percentile 18 ()
State
PUBLISHED
Published
Updated
Assigner
juniper
NVD status
Modified

Description

An Improper Handling of Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS allows an unauthenticated, network-adjacent attacker sending a specifically malformed ICMP packet to cause an FPC to crash and restart, resulting in a Denial of Service (DoS). When an ICMP packet is received with a specifically malformed IP header value, the FPC receiving the packet crashes and restarts. Due to the specific type of malformed packet, adjacent upstream routers would not forward the packet, limiting the attack surface to adjacent networks. This issue only affects ICMPv4. ICMPv6 is not vulnerable to this issue. This issue does not affect AFT-based line cards such as the MPC10, MPC11, LC4800, LC9600, and MX304. This issue affects Junos OS:  * all versions before 21.2R3-S9,  * from 21.4 before 21.4R3-S10,  * from 22.2 before 22.2R3-S7,  * from 22.3 before 22.3R3-S4,  * from 22.4 before 22.4R3-S5,  * from 23.2 before 23.2R2-S3,  * from 23.4 before 23.4R2-S3,  * from 24.2 before 24.2R1-S2, 24.2R2.

Weaknesses (CWE)

  • CWE-755 — Improper Handling of Exceptional Conditions

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hjuniper
CVSS 4.0HIGH 7.1CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:A/RE:M/U:Amberjuniper
CVSS 4.0HIGH 7.1CVSS:4.0/AV:A/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:Y/R:A/V:X/RE:M/U:AmberNVD · sirt@juniper.net (Secondary)
CVSS 3.1MEDIUM 6.5CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · sirt@juniper.net (Secondary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Juniper Networks · Junos OSaffected 0 < 21.2R3-S9 ; affected 21.4 < 21.4R3-S10 ; affected 22.2 < 22.2R3-S7 ; affected 22.3 < 22.3R3-S4 ; affected 22.4 < 22.4R3-S5 ; affected 23.2 < 23.2R2-S3

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD