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TI-2020-01633 Aliases CVE-2020-1686GHSA-2j3x-ghj2-35fv

Junos OS: Kernel crash (vmcore) upon receipt of a malformed IPv6 packet.

Priority LOW 36CWE-415Published · Updated

Key facts

Attack vector
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-415 and the CVSS impact.

Summary

On Juniper Networks Junos OS devices, receipt of a malformed IPv6 packet may cause the system to crash and restart (vmcore). This issue can be trigged by a malformed IPv6 packet destined to the Routing Engine. An attacker can repeatedly send the offending packet resulting in an extended Denial of Service condition. Only IPv6 packets can trigger this issue. IPv4 packets cannot trigger this issue. This issue affects Juniper Networks Junos OS 18.4 versions prior to 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R2-S1, 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 prior to 18.4R1.

Why it matters now

EPSS 0.01399 72nd percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 18.4R2-S4, 18.4R3-S1, 19.1R2-S1 +7

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS18.4 to before 18.4R2-S4, 18.4R3-S1; 19.1 to before 19.1R2-S1, 19.1R3; 19.2 to before 19.2R1-S5, 19.2R2; 19.3 to before 19.3R2-S4, 19.3R3; 19.4 to before 19.4R1-S3, 19.4R218.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2Patch availableCNA
  • Junos OS VendorJuniper Affected 18.4 to before 18.4R2-S4, 18.4R3-S1; 19.1 to before 19.1R2-S1, 19.1R3; 19.2 to before 19.2R1-S5, 19.2R2; 19.3 to before 19.3R2-S4, 19.3R3; 19.4 to before 19.4R1-S3, 19.4R2 Fixed in 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2 Patch available CNA

CPE configurations NVD · 34

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:18.4:-:*:*:*:*:*:*18.4VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r1:*:*:*:*:*:*18.4 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r1-s1:*:*:*:*:*:*18.4 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r1-s2:*:*:*:*:*:*18.4 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r1-s5:*:*:*:*:*:*18.4 r1-s5VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r1-s6:*:*:*:*:*:*18.4 r1-s6VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r2:*:*:*:*:*:*18.4 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r2-s1:*:*:*:*:*:*18.4 r2-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r2-s2:*:*:*:*:*:*18.4 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:18.4:r2-s3:*:*:*:*:*:*18.4 r2-s3VulnerableJuniper
  • cpe:2.3:o:juniper:junos:18.4:-:*:*:*:*:*:* Versions 18.4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r1:*:*:*:*:*:* Versions 18.4 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r1-s1:*:*:*:*:*:* Versions 18.4 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r1-s2:*:*:*:*:*:* Versions 18.4 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r1-s5:*:*:*:*:*:* Versions 18.4 r1-s5 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r1-s6:*:*:*:*:*:* Versions 18.4 r1-s6 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r2:*:*:*:*:*:* Versions 18.4 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r2-s1:*:*:*:*:*:* Versions 18.4 r2-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r2-s2:*:*:*:*:*:* Versions 18.4 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:18.4:r2-s3:*:*:*:*:*:* Versions 18.4 r2-s3 Vulnerable ·Juniper
Show 24 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos:18.4:r3:*:*:*:*:*:*18.4 r3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:-:*:*:*:*:*:*19.1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r1:*:*:*:*:*:*19.1 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r1-s1:*:*:*:*:*:*19.1 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r1-s2:*:*:*:*:*:*19.1 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r1-s3:*:*:*:*:*:*19.1 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r1-s4:*:*:*:*:*:*19.1 r1-s4VulnerableJuniper
cpe:2.3:o:juniper:junos:19.1:r2:*:*:*:*:*:*19.1 r2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:-:*:*:*:*:*:*19.2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1:*:*:*:*:*:*19.2 r1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1-s1:*:*:*:*:*:*19.2 r1-s1VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1-s2:*:*:*:*:*:*19.2 r1-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1-s3:*:*:*:*:*:*19.2 r1-s3VulnerableJuniper
cpe:2.3:o:juniper:junos:19.2:r1-s4:*:*:*:*:*:*19.2 r1-s4VulnerableJuniper
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:19.3: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:19.4: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:18.4:r3:*:*:*:*:*:* Versions 18.4 r3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:-:*:*:*:*:*:* Versions 19.1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r1:*:*:*:*:*:* Versions 19.1 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r1-s1:*:*:*:*:*:* Versions 19.1 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r1-s2:*:*:*:*:*:* Versions 19.1 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r1-s3:*:*:*:*:*:* Versions 19.1 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r1-s4:*:*:*:*:*:* Versions 19.1 r1-s4 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.1:r2:*:*:*:*:*:* Versions 19.1 r2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:-:*:*:*:*:*:* Versions 19.2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1:*:*:*:*:*:* Versions 19.2 r1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1-s1:*:*:*:*:*:* Versions 19.2 r1-s1 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1-s2:*:*:*:*:*:* Versions 19.2 r1-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1-s3:*:*:*:*:*:* Versions 19.2 r1-s3 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:19.2:r1-s4:*:*:*:*:*:* Versions 19.2 r1-s4 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
  • 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:19.4: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

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 18.4R2-S4, 18.4R3-S1, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S4, 19.3R3, 19.4R1-S3, 19.4R2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2020-1686
  2. 2026-10-03 Alias added: GHSA-2j3x-ghj2-35fv

References

  • 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