CVE-2021-31362mediumCWE-693

CVE-2021-31362: medium-severity vulnerability in Juniper Networks Junos OS

Junos OS and Junos OS Evolved: An IS-IS adjacency might be taken down if a bad hello PDU is received for an existing adjacency causing a DoS

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.4%
A Protection Mechanism Failure vulnerability in RPD (routing protocol daemon) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause established IS-IS adjacencies to go down by sending a spoofed hello PDU leading to a Denial of Service (DoS) condition. Continued receipted of these spoofed PDUs will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS All versions prior to 18.2R3-S8; 18.3 versions prior to 18.3R3-S5; 18.4 versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S7; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R3-S3; 20.1 versions prior to 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2. Juniper Networks Junos OS Evolved All versions prior to 20.4R2-EVO; 21.1 versions prior to 21.1R2-EVO.
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Juniper Networks · Junos OSJuniper Networks · Junos OS Evolved
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