CVE-2021-0290

Junos OS: MX Series, EX9200 Series, SRX4600: Ethernet interface vulnerable to specially crafted frames

Description

Improper Handling of Exceptional Conditions in Ethernet interface frame processing of Juniper Networks Junos OS allows an attacker to send specially crafted frames over the local Ethernet segment, causing the interface to go into a down state, resulting in a Denial of Service (DoS) condition. The interface does not recover on its own and the FPC must be reset manually. Continued receipt and processing of these frames will create a sustained Denial of Service (DoS) condition. This issue is platform-specific and affects the following platforms and line cards: * MPC7E/8E/9E and MPC10E on MX240, MX480, MX960, MX2008, MX2010, and MX2020 * MX204, MX10003, MX10008, MX10016 * EX9200, EX9251 * SRX4600 No other products or platforms are affected by this vulnerability. An indication of this issue occurring can be seen in the system log messages, as shown below: user@host> show log messages | match "Failed to complete DFE tuning" fpc4 smic_phy_dfe_tuning_state: et-4/1/6 - Failed to complete DFE tuning (count 3) and interface will be in a permanently down state: user@host> show interfaces et-4/1/6 terse Interface Admin Link Proto Local Remote et-4/1/6 up down et-4/1/6.0 up down aenet --> ae101.0 This issue affects Juniper Networks Junos OS: 16.1 versions prior to 16.1R7-S7 on MX Series; 17.1R1 and later versions prior to 17.2R3-S3 on MX Series; 17.3 versions prior to 17.3R3-S8 on MX Series; 17.4 versions prior to 17.4R2-S11, 17.4R3-S1 on MX Series, SRX4600; 18.1 versions prior to 18.1R3-S10 on MX Series, EX9200 Series, SRX4600; 18.2 versions prior to 18.2R3-S3 on MX Series, EX9200 Series, SRX4600; 18.3 versions prior to 18.3R3-S1 on MX Series, EX9200 Series, SRX4600; 18.4 versions prior to 18.4R2-S3, 18.4R3 on MX Series, EX9200 Series, SRX4600; 19.1 versions prior to 19.1R2-S1, 19.1R3 on MX Series, EX9200 Series, SRX4600; 19.2 versions prior to 19.2R1-S3, 19.2R2 on MX Series, EX9200 Series, SRX4600; 19.3 versions prior to 19.3R2 on MX Series, EX9200 Series, SRX4600. This issue does not affect Juniper Networks Junos OS versions prior to 16.1R1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS 16.1R7-S7, 17.2R3-S3, 17.3R3-S8, 17.4R2-S11, 17.4R3-S1, 17.4R3-S5, 18.1R3-S10, 18.2R3-S3, 18.2R3-S8, 18.3R3-S1, 18.4R2-S3, 18.4R3, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.08%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11192 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0290?
CVE-2021-0290 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0290?
To fix CVE-2021-0290: The following software releases have been updated to resolve this specific issue: Junos OS 16.1R7-S7, 17.2R3-S3, 17.3R3-S8, 17.4R2-S11, 17.4R3-S1, 17.4R3-S5, 18.1R3-S10, 18.2R3-S3, 18.2R3-S8, 18.3R3-S1, 18.4R2-S3, 18.4R3, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.
Is CVE-2021-0290 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0290 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-0290?
CVE-2021-0290 affects Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS, Juniper Networks Junos OS.
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