Vulnerability identifier: #VU54988

Vulnerability risk: Medium

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

CVE-ID: CVE-2021-0287

CWE-ID: CWE-399

Exploitation vector: Local network

Exploit availability: No

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

Vendor: Juniper Networks, Inc.

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper management of internal resources within the application. In an Segment Routing ISIS (SR-ISIS)/MPLS environment, on Juniper Networks Junos OS and Junos OS Evolved devices, configured with ISIS Flexible Algorithm for Segment Routing and sensor-based statistics, a flap of a ISIS link in the network, can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued link flaps will create a sustained Denial of Service (DoS) condition.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Junos OS Evolved: 21.1 - 21.1-EVO, 20.4 - 20.4R1-S2-EVO, 20.3 - 20.3R1-S2-EVO

Juniper Junos OS: 19.4 - 19.4R3-S1, 19.4R1 - 19.4R1-S3, 20.1 - 20.1R2-S2, 20.2 - 20.2R2-S3, 20.4, 20.3 - 20.3R1-S2

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External links
http://kb.juniper.net/JSA11189

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

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