Vulnerability identifier: #VU52286

Vulnerability risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-0236

CWE-ID: CWE-754

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Juniper Junos OS
Operating systems & Components / Operating system
Junos OS Evolved
Operating systems & Components / Operating system

Vendor: Juniper Networks, Inc.

Description

The vulnerability allows a remote user to perform denial of service attack.

The vulnerability exists due to improper check for unusual or exceptional conditions within the Routing Protocol Daemon (RPD) service when handling BGP VPNv6 flowspec messages. A remote user attacker can send specific matching BGP packet, which meets a specific term in the flowspec configuration and crash the service.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 19.4 - 19.4R3, 19.4R1 - 19.4R1-S4, 19.3 - 19.3R3-S1, 19.3R1-S1, 19.3R2 - 19.3R2-S7, 18.4 - 18.4R3-S6, 18.4R1-S5, 18.4R2-S3, 19.2 - 19.2R3-S1, 19.2R1-S4, 20.2 - 20.2R2-S3, 20.1 - 20.1R2-S2, 19.1 - 19.1R3-S3, 19.1R1-S4, 20.4, 20.3 - 20.3R1-S2

Junos OS Evolved: 20.4, 20.3 - 20.3R1-S2-EVO

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External links
http://kb.juniper.net/InfoCenter/index?page=content&id=JSA11131&cat=SIRT_1&actp=LIST

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.