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TI-2021-00220 Aliases CVE-2021-0287GHSA-rr23-qf6q-44wq

Junos OS and Junos OS Evolved: RPD could crash in SR-ISIS/MPLS environment due to a flap of an ISIS link in the network

Priority LOW 29CWE-754Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

In a 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. This issue affects: Juniper Networks Junos OS: 19.4 versions prior to 19.4R1-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R2; Juniper Networks Junos OS Evolved: 20.3-EVO versions prior to 20.3R2-EVO; 20.4-EVO versions prior to 20.4R2-EVO. This issue does not affect: Juniper Networks Junos OS releases prior to 19.4R1. Juniper Networks Junos OS Evolved releases prior to 19.4R1-EVO.

Why it matters now

EPSS 0.00374 31st percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 20.1R2-S1, 20.1R3, 20.2R2-S2 +2Junos OS Evolved (Juniper Networks): 20.3R2-EVO, 20.4R2-EVO

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS19.4R1 and later; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R2-S2, 20.2R3; 20.3 to before 20.3R220.1R2-S1, 20.1R3, 20.2R2-S2, 20.2R3, 20.3R2Patch availableCNA
JuniperJunos OS Evolved19.4R1-EVO and later; 20.1R1-EVO and later; 20.2R1-EVO and later; 20.3 to before 20.3R2-EVO; 20.4 to before 20.4R2-EVO20.3R2-EVO, 20.4R2-EVOPatch availableCNA
  • Junos OS VendorJuniper Affected 19.4R1 and later; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R2-S2, 20.2R3; 20.3 to before 20.3R2 Fixed in 20.1R2-S1, 20.1R3, 20.2R2-S2, 20.2R3, 20.3R2 Patch available CNA
  • Junos OS Evolved VendorJuniper Affected 19.4R1-EVO and later; 20.1R1-EVO and later; 20.2R1-EVO and later; 20.3 to before 20.3R2-EVO; 20.4 to before 20.4R2-EVO Fixed in 20.3R2-EVO, 20.4R2-EVO Patch available CNA

CPE configurations NVD · 27

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:19.4:r1:*:*:*:*:*:*19.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r1-s1:*:*:*:*:*:*19.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r1-s2:*:*:*:*:*:*19.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r1-s3:*:*:*:*:*:*19.4 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2:*:*:*:*:*:*19.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2-s1:*:*:*:*:*:*19.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2-s2:*:*:*:*:*:*19.4 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r2-s3:*:*:*:*:*:*19.4 r2-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r3:*:*:*:*:*:*19.4 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r3-s1:*:*:*:*:*:*19.4 r3-s1VulnerableJuniper
  • cpe:2.3:o:juniper:junos:19.4:r1:*:*:*:*:*:* Versions 19.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r1-s1:*:*:*:*:*:* Versions 19.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r1-s2:*:*:*:*:*:* Versions 19.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r1-s3:*:*:*:*:*:* Versions 19.4 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2:*:*:*:*:*:* Versions 19.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2-s1:*:*:*:*:*:* Versions 19.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2-s2:*:*:*:*:*:* Versions 19.4 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r2-s3:*:*:*:*:*:* Versions 19.4 r2-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r3:*:*:*:*:*:* Versions 19.4 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r3-s1:*:*:*:*:*:* Versions 19.4 r3-s1 Vulnerable ·Juniper
Show 17 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:20.1:r1:*:*:*:*:*:*20.1 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r1-s1:*:*:*:*:*:*20.1 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r1-s2:*:*:*:*:*:*20.1 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r1-s3:*:*:*:*:*:*20.1 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r1-s4:*:*:*:*:*:*20.1 r1-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:20.1:r2:*:*:*:*:*:*20.1 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r1:*:*:*:*:*:*20.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r1-s1:*:*:*:*:*:*20.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r1-s2:*:*:*:*:*:*20.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r1-s3:*:*:*:*:*:*20.2 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r2:*:*:*:*:*:*20.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r2-s1:*:*:*:*:*:*20.2 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.3:r1:*:*:*:*:*:*20.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:20.3:r1-s1:*:*:*:*:*:*20.3 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.3:-:*:*:*:*:*:*20.3VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.3:r1:*:*:*:*:*:*20.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.4:r1-s1:*:*:*:*:*:*20.4 r1-s1VulnerableJuniper
  • cpe:2.3:o:juniper:junos:20.1:r1:*:*:*:*:*:* Versions 20.1 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r1-s1:*:*:*:*:*:* Versions 20.1 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r1-s2:*:*:*:*:*:* Versions 20.1 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r1-s3:*:*:*:*:*:* Versions 20.1 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r1-s4:*:*:*:*:*:* Versions 20.1 r1-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.1:r2:*:*:*:*:*:* Versions 20.1 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r1:*:*:*:*:*:* Versions 20.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r1-s1:*:*:*:*:*:* Versions 20.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r1-s2:*:*:*:*:*:* Versions 20.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r1-s3:*:*:*:*:*:* Versions 20.2 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r2:*:*:*:*:*:* Versions 20.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r2-s1:*:*:*:*:*:* Versions 20.2 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.3:r1:*:*:*:*:*:* Versions 20.3 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.3:r1-s1:*:*:*:*:*:* Versions 20.3 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.3:-:*:*:*:*:*:* Versions 20.3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.3:r1:*:*:*:*:*:* Versions 20.3 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.4:r1-s1:*:*:*:*:*:* Versions 20.4 r1-s1 Vulnerable ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 20.1R2-S1, 20.1R3, 20.2R2-S2, 20.2R3, 20.3R2
  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 20.3R2-EVO, 20.4R2-EVO

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-0287
  2. 2026-10-03 Alias added: GHSA-rr23-qf6q-44wq

References

Advisory 1

  • TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
  • TI-2023-18644 Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload and download arbitrary files KEVCVSS 3.1MEDIUM 5.3
  • TI-2023-18640 Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files KEVCVSS 3.1MEDIUM 5.3
See all 792 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences