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TI-2021-00201 Aliases CVE-2021-0267GHSA-m6p4-4cgp-9hfh

Junos OS: Receipt of a crafted DHCP packet will cause the jdhcpd DHCP service to core.

Priority LOW 33CWE-20Published · 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

An Improper Input Validation vulnerability in the active-lease query portion in JDHCPD's DHCP Relay Agent of Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) by sending a crafted DHCP packet to the device thereby crashing the jdhcpd DHCP service. This is typically configured for Broadband Subscriber Sessions. Continued receipt and processing of this crafted packet will create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS: 19.4 versions prior to 19.4R3-S1; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R3; 20.3 versions prior to 20.3R2. This issue does not affect Junos OS Evolved.

Why it matters now

EPSS 0.00466 40th percentileScored 2026-11-07
Fix Fixed Junos OS (Juniper Networks): 19.4R3-S1, 20.1R2-S1, 20.1R3 +2

SSVC decision points

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

Affected products

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS19.4 to before 19.4R3-S1; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R3; 20.3 to before 20.3R219.4R3-S1, 20.1R2-S1, 20.1R3, 20.2R3, 20.3R2Patch availableCNA
  • Junos OS VendorJuniper Affected 19.4 to before 19.4R3-S1; 20.1 to before 20.1R2-S1, 20.1R3; 20.2 to before 20.2R3; 20.3 to before 20.3R2 Fixed in 19.4R3-S1, 20.1R2-S1, 20.1R3, 20.2R3, 20.3R2 Patch available CNA

CPE configurations NVD · 23

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: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:r3:*:*:*:*:*:*19.4 r3VulnerableJuniper
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: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: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:r3:*:*:*:*:*:* Versions 19.4 r3 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
Show 13 more CPE
CPEVersionsRoleVendor
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:20.2:r2-s2:*:*:*:*:*:*20.2 r2-s2VulnerableJuniper
cpe:2.3:o:juniper:junos:20.2:r2-s3:*:*:*:*:*:*20.2 r2-s3VulnerableJuniper
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:20.1: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:20.2:r2-s2:*:*:*:*:*:* Versions 20.2 r2-s2 Vulnerable ·Juniper
  • cpe:2.3:o:juniper:junos:20.2:r2-s3:*:*:*:*:*:* Versions 20.2 r2-s3 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

Remediation

  • Fix · CNA Junos OS (Juniper Networks) Fixed in 19.4R3-S1, 20.1R2-S1, 20.1R3, 20.2R3, 20.3R2

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-0267
  2. 2026-10-03 Alias added: GHSA-m6p4-4cgp-9hfh

References

Advisory 2

  • 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