CVE-2021-0271

Junos OS: EX2200-C Series, EX3200 Series, EX3300 Series, EX4200 Series, EX4500 Series, EX4550 Series, EX6210 Series, EX8208 Series, EX8216 Series: Receipt of a crafted ARP packet by an adjacent attacker will cause the sfid process to core.

MEDIUM
6.5
CVSS Score
Published: April 22, 2021 at 07:37 PM UTC
Updated: June 17, 2026 at 03:29 AM UTC
10 products affected across 2 vendorsJunosEx4200Ex4550

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.4%

Description

A Double Free vulnerability in the software forwarding interface daemon (sfid) process of Juniper Networks Junos OS allows an adjacently-connected attacker to cause a Denial of Service (DoS) by sending a crafted ARP packet to the device. Continued receipt and processing of the crafted ARP packets will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on EX2200-C Series, EX3200 Series, EX3300 Series, EX4200 Series, EX4500 Series, EX4550 Series, EX6210 Series, EX8208 Series, EX8216 Series. 12.3 versions prior to 12.3R12-S17; 15.1 versions prior to 15.1R7-S8. This issue only affects the listed Marvell-chipset based EX Series devices. No other products or platforms are affected.

Affected

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

Affected range stops below 12.3R12-S17, so it looks safe — our inference, not a vendor statement
Affected range stops below 15.1R7-S8, so it looks safe — our inference, not a vendor statement
juniper-ex2200-c (environment) · juniper-ex3200 (environment) · juniper-ex3300 (environment) · juniper-ex4200 (environment) · juniper-ex4500 (environment) · juniper-ex4550 (environment) · juniper-ex6210 (environment) · juniper-ex8208 (environment) · juniper-ex8216 (environment)
All versions
All versions
All versions
All versions
All versions
All versions
All versions
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/JSA11162

CVSS

6.5MEDIUMjuniper
Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-415

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