Vulnerability · Published Apr 22, 2021 · Assigned by juniper

CVE-2021-0258Junos OS: Kernel panic upon receipt of specific TCPv6 packet on management interface

Medium 5.9

In plain English

A medium-severity race condition in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 51% of all known vulnerabilities).

Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.6%top 48.8% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

A vulnerability in the forwarding of transit TCPv6 packets received on the Ethernet management interface of Juniper Networks Junos OS allows an attacker to trigger a kernel panic, leading to a Denial of Service (DoS). Continued receipt and processing of these transit packets will create a sustained Denial of Service (DoS) condition. This issue only occurs when TCPv6 packets are routed through the management interface. Other transit traffic, and traffic destined to the management interface, are unaffected by this vulnerability. This issue was introduced as part of a TCP Parallelization feature added in Junos OS 17.2, and affects systems with concurrent network stack enabled. This feature is enabled by default, but can be disabled (see WORKAROUND section below). This issue affects Juniper Networks Junos OS: 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.

Affected products (as reported)

VendorProductVersions
Juniper Networks Junos OS 17.3 – before 17.3R3-S917.4 – before 17.4R2-S11, 17.4R3-S218.1 – before 18.1R3-S1118.2 – before 18.2R3-S518.3 – before 18.3R2-S4, 18.3R3-S318.4 – before 18.4R2-S5, 18.4R3-S419.1 – before 19.1R2-S2, 19.1R3

Weakness: CWE-362 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References