CVE-2021-0206

Junos OS: NFX Series, SRX Series: PFE may crash upon receipt of specific packet when SSL Proxy is configured.

Description

A NULL Pointer Dereference vulnerability in Juniper Networks Junos OS allows an attacker to send a specific packet causing the packet forwarding engine (PFE) to crash and restart, resulting in a Denial of Service (DoS). By continuously sending these specific packets, an attacker can repeatedly disable the PFE causing a sustained Denial of Service (DoS). This issue only affects Juniper Networks NFX Series, SRX Series platforms when SSL Proxy is configured. This issue affects Juniper Networks Junos OS on NFX Series and SRX Series: 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R3-S1; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S2, 19.2R2; 19.3 versions prior to 19.3R2. This issue does not affect Juniper Networks Junos OS versions on NFX Series and SRX Series prior to 18.3R1.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS: 18.3R3-S4, 18.4R3-S1, 19.1R1-S6, 19.1R2-S2, 19.1R3, 19.2R1-S2, 19.2R2, 19.3R2, 19.4R1 and all subsequent releases.

Workaround:

  • There are no viable workarounds for this issue.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.39%
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11096 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0206?
CVE-2021-0206 has been scored as a high severity vulnerability.
How to fix CVE-2021-0206?
To fix CVE-2021-0206: The following software releases have been updated to resolve this specific issue: Junos OS: 18.3R3-S4, 18.4R3-S1, 19.1R1-S6, 19.1R2-S2, 19.1R3, 19.2R1-S2, 19.2R2, 19.3R2, 19.4R1 and all subsequent releases.
Is CVE-2021-0206 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0206 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-2021-0206?
CVE-2021-0206 affects Juniper Networks Junos OS.
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