CVE-2021-0209

Junos OS Evolved: Receipt of certain valid BGP update packets from BGP peers may cause RPD to core when using REGEX.

Description

In Juniper Networks Junos OS Evolved an attacker sending certain valid BGP update packets may cause Junos OS Evolved to access an uninitialized pointer causing RPD to core leading to a Denial of Service (DoS). Continued receipt of these types of valid BGP update packets will cause an extended Denial of Service condition. RPD will require a restart to recover. An indicator of compromise is to see if the file rpd.re exists by issuing the command: show system core-dumps This issue affects: Juniper Networks Junos OS Evolved 19.4 versions prior to 19.4R2-S2-EVO; 20.1 versions prior to 20.1R1-S2-EVO, 20.1R2-S1-EVO. This issue does not affect Junos OS.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: Junos OS Evolved: 19.4R2-S2-EVO, 20.1R1-S2-EVO, 20.1R2-S1-EVO, 20.2R1-EVO and all subsequent releases.

Workaround:

  • There are no available 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 Evolved
Published at:
Updated at:

References

Link Tags
https://kb.juniper.net/JSA11099 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-0209?
CVE-2021-0209 has been scored as a medium severity vulnerability.
How to fix CVE-2021-0209?
To fix CVE-2021-0209: The following software releases have been updated to resolve this specific issue: Junos OS Evolved: 19.4R2-S2-EVO, 20.1R1-S2-EVO, 20.1R2-S1-EVO, 20.2R1-EVO and all subsequent releases.
Is CVE-2021-0209 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-0209 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-2021-0209?
CVE-2021-0209 affects Juniper Networks Junos OS Evolved.
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