CVE-2021-0233

Junos OS: ACX500 Series, ACX4000 Series: Denial of Service due to FFEB crash while processing high rate of specific packets.

HIGH
7.5
CVSS Score
Published: April 22, 2021 at 07:37 PM UTC
Updated: June 17, 2026 at 03:29 AM UTC
3 products affected across 2 vendorsJunosAcx500Acx4000

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Severity
HIGH7.5
Exploit prediction
EPSS 1.0%

Description

A vulnerability in Juniper Networks Junos OS ACX500 Series, ACX4000 Series, may allow an attacker to cause a Denial of Service (DoS) by sending a high rate of specific packets to the device, resulting in a Forwarding Engine Board (FFEB) crash. Continued receipt of these packets will sustain the Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS on ACX500 Series, ACX4000 Series: 17.4 versions prior to 17.4R3-S2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Affected range stops below 17.4R3-S2, so it looks safe — our inference, not a vendor statement
juniper-acx4000 (environment) · juniper-acx500 (environment)
All versions
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (1)

x_refsource_MISCVendor Advisory
https://kb.juniper.net/JSA11128

CVSS

7.5HIGHjuniper
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-400CWE-794NVD-CWE-noinfo

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