Home/CVE/A Protection Mechanism Failure vulnerability in RPD (routing protocol daemon) of Juniper Networks Junos OS and Junos OS
CVE

CVE-2021-31362

A Protection Mechanism Failure vulnerability in RPD (routing protocol daemon) of Juniper Networks Junos OS and Junos OS

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.

MEDIUM · CVSS 6.5 EPSS 0.00084
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-693Protection Mechanism Failure
▤

Affected Products & Versions

2
juniper junos<= 18.1
juniper junosall versions
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · sirt@juniper.net
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD19 Oct 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://kb.juniper.net/JSA11224Vendor Advisory
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