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TI-2021-11507 Aliases CVE-2021-31363GHSA-mh4w-qhp7-f8v8

Junos OS and Junos OS Evolved: Receipt of a specific LDP message will cause a Denial of Service

Priority LOW 29CWE-835Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-835.

Summary

In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO.

Why it matters now

EPSS 0.00404 34th percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 19.3R2-S6, 19.3R3-S2, 19.4R1-S4 +8Junos OS Evolved (Juniper Networks): 20.1R2-S3-EVO, 20.3R1-S2-EVO

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS19.2R2 and later; 19.3 to before 19.3R2-S6, 19.3R3-S2; 19.4 to before 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R2-S1, 20.2R3; 20.3 to before 20.3R1-S2, 20.3R219.3R2-S6, 19.3R3-S2, 19.4R1-S4, 19.4R2-S4, 19.4R3-S2, 20.1R2-S1, 20.1R3, 20.2R2-S1, 20.2R3, 20.3R1-S2, 20.3R2Patch availableCNA
JuniperJunos OS Evolvedbefore 20.1R2-S3-EVO; 20.3 to before 20.3R1-S2-EVO20.1R2-S3-EVO, 20.3R1-S2-EVOPatch availableCNA
  • Junos OS VendorJuniper Affected 19.2R2 and later; 19.3 to before 19.3R2-S6, 19.3R3-S2; 19.4 to before 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R2-S1, 20.2R3; 20.3 to before 20.3R1-S2, 20.3R2 Fixed in 19.3R2-S6, 19.3R3-S2, 19.4R1-S4, 19.4R2-S4, 19.4R3-S2, 20.1R2-S1, 20.1R3, 20.2R2-S1, 20.2R3, 20.3R1-S2, 20.3R2 Patch available CNA
  • Junos OS Evolved VendorJuniper Affected before 20.1R2-S3-EVO; 20.3 to before 20.3R1-S2-EVO Fixed in 20.1R2-S3-EVO, 20.3R1-S2-EVO Patch available CNA

CPE configurations NVD · 47

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:19.2:r2:*:*:*:*:*:*19.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r2-s1:*:*:*:*:*:*19.2 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r3:*:*:*:*:*:*19.2 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r3-s1:*:*:*:*:*:*19.2 r3-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r3-s2:*:*:*:*:*:*19.2 r3-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:-:*:*:*:*:*:*19.3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r1:*:*:*:*:*:*19.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r1-s1:*:*:*:*:*:*19.3 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r2:*:*:*:*:*:*19.3 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r2-s1:*:*:*:*:*:*19.3 r2-s1VulnerableJuniper
  • cpe:2.3:o:juniper:junos:19.2:r2:*:*:*:*:*:* Versions 19.2 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r2-s1:*:*:*:*:*:* Versions 19.2 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r3:*:*:*:*:*:* Versions 19.2 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r3-s1:*:*:*:*:*:* Versions 19.2 r3-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r3-s2:*:*:*:*:*:* Versions 19.2 r3-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:-:*:*:*:*:*:* Versions 19.3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r1:*:*:*:*:*:* Versions 19.3 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r1-s1:*:*:*:*:*:* Versions 19.3 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r2:*:*:*:*:*:* Versions 19.3 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r2-s1:*:*:*:*:*:* Versions 19.3 r2-s1 Vulnerable ·Juniper
Show 37 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:19.3:r2-s2:*:*:*:*:*:*19.3 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r2-s3:*:*:*:*:*:*19.3 r2-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r2-s4:*:*:*:*:*:*19.3 r2-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r2-s5:*:*:*:*:*:*19.3 r2-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:19.3:r3-s2:*:*:*:*:*:*19.3 r3-s2VulnerableJuniper
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-s4:*:*:*:*:*:*19.4 r2-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:19.4:r3-s2:*:*:*:*:*:*19.4 r3-s2VulnerableJuniper
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:20.1:r3:*:*:*:*:*:*20.1 r3VulnerableJuniper
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:r3:*:*:*:*:*:*20.2 r3VulnerableJuniper
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:20.3:r2:*:*:*:*:*:*20.3 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.1:r1:*:*:*:*:*:*20.1 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.1:r1-s1:*:*:*:*:*:*20.1 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.1:r2:*:*:*:*:*:*20.1 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s1:*:*:*:*:*:*20.1 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s2:*:*:*:*:*:*20.1 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.2:r1:*:*:*:*:*:*20.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.2:r1-s1:*:*:*:*:*:*20.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.2:r2:*:*:*:*:*:*20.2 r2VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.3:r1:*:*:*:*:*:*20.3 r1VulnerableJuniper
cpe:2.3:o:juniper:junos_os_evolved:20.3:r1-s1:*:*:*:*:*:*20.3 r1-s1VulnerableJuniper
  • cpe:2.3:o:juniper:junos:19.3:r2-s2:*:*:*:*:*:* Versions 19.3 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r2-s3:*:*:*:*:*:* Versions 19.3 r2-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r2-s4:*:*:*:*:*:* Versions 19.3 r2-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r2-s5:*:*:*:*:*:* Versions 19.3 r2-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.3:r3-s2:*:*:*:*:*:* Versions 19.3 r3-s2 Vulnerable ·Juniper
  • 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-s4:*:*:*:*:*:* Versions 19.4 r2-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.4:r3-s2:*:*:*:*:*:* Versions 19.4 r3-s2 Vulnerable ·Juniper
  • 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:20.1:r3:*:*:*:*:*:* Versions 20.1 r3 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:r3:*:*:*:*:*:* Versions 20.2 r3 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:20.3:r2:*:*:*:*:*:* Versions 20.3 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.1:r1:*:*:*:*:*:* Versions 20.1 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.1:r1-s1:*:*:*:*:*:* Versions 20.1 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.1:r2:*:*:*:*:*:* Versions 20.1 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s1:*:*:*:*:*:* Versions 20.1 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.1:r2-s2:*:*:*:*:*:* Versions 20.1 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.2:r1:*:*:*:*:*:* Versions 20.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.2:r1-s1:*:*:*:*:*:* Versions 20.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:20.2:r2:*:*:*:*:*:* Versions 20.2 r2 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:20.3:r1-s1:*:*:*:*:*:* Versions 20.3 r1-s1 Vulnerable ·Juniper

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 19.3R2-S6, 19.3R3-S2, 19.4R1-S4, 19.4R2-S4, 19.4R3-S2, 20.1R2-S1, 20.1R3, 20.2R2-S1, 20.2R3, 20.3R1-S2, 20.3R2
  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 20.1R2-S3-EVO, 20.3R1-S2-EVO

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-31363
  2. 2026-10-03 Alias added: GHSA-mh4w-qhp7-f8v8

References

Patch 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

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