Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2021-0222 — juniper / junos

Configuration

A vulnerability in Juniper Networks Junos OS allows an attacker to cause a Denial of Service (DoS) to the device by sending certain crafted protocol packets from an adjacent device with invalid payloads to the device. These crafted packets, which should be discarded, are instead replicated and sent to the RE. Over time, a Denial of Service (DoS) occurs. Continued receipt of these crafted protocol packets will cause an extended Denial of Service (DoS) condition, which may cause wider traffic impact due to protocol flapping. An indication of compromise is to check "monitor interface traffic" on the ingress and egress port packet counts. For each ingress packet, two duplicate packets are seen on egress. This issue can be triggered by IPv4 and IPv6 packets. This issue affects all traffic through the device. This issue affects: Juniper Networks Junos OS: 14.1X53 versions prior to 14.1X53-D53 on EX4300, QFX3500, QFX5100, EX4600; 15.1 versions prior to 15.1R7-S6 on EX4300, QFX3500, QFX5100, EX4600; 16.1 versions prior to 16.1R7-S7 on EX4300, QFX5100, EX4600; 17.1 versions prior to 17.1R2-S11 on EX4300, QFX5100, EX4600; 17.1 versions prior to 117.1R3-S2 on EX4300; 17.2 versions prior to 17.2R1-S9 on EX4300; 17.2 versions prior to 17.2R3-S3 on EX4300, QFX5100, EX4600, QFX5110, QFX5200; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7 on EX4300, QFX5100, EX4600, QFX5110, QFX5200; 17.4 versions prior to 17.4R2-S9, 17.4R3 on EX4300, QFX5100, EX4600, QFX5110, QFX5200; 18.1 versions prior to 18.1R3-S9 on EX4300, QFX5100, EX4600, QFX5110, QFX5200, QFX5210, EX2300, EX3400; 18.2 versions prior to 18.2R2-S7 on EX4300; 18.2 versions prior to 18.2R3-S3 on EX4300, QFX5100, EX4600, QFX5110, QFX5200, QFX5210, EX2300, EX3400; 18.3 versions prior to 18.3R2-S3, on EX4300; 18.3 versions prior to 18.3R1-S7, 18.3R3-S1 on EX4300, QFX5100, EX4600, QFX5110, QFX5200, QFX5210, QFX5120, EX4650, EX2300, EX3400; 18.4 versions prior to 18.4R1-S5, 18.4R2-S3, 18.4R3 on EX4300, QFX5100, EX4600, QFX5110, QFX5200, QFX5210, QFX5120, EX4650, EX2300, EX3400; 19.1 versions prior to 19.1R1-S4, 19.1R2-S1, 19.1R3 on EX4300, QFX5100, EX4600, QFX5110, QFX5200, QFX5210, QFX5120, EX4650, EX2300, EX3400; 19.2 versions prior to 19.2R1-S4, 19.2R2 on EX4300; 19.2 versions prior to 19.2R1-S3, 19.2R2 on QFX5100, EX4600, QFX5110, QFX5200, QFX5210, QFX5120, EX4650, EX2300, EX3400; 19.3 versions prior to 19.3R2-S1, 19.3R3 on EX4300; 19.3 versions prior to 19.3R1-S1, 19.3R2, 19.3R3 on QFX5100, EX4600, QFX5110, QFX5200, QFX5210, QFX5120, EX4650, EX2300, EX3400;

  • Published: Jan 15, 2021
  • Updated: Nov 16, 2025
  • CVE: CVE-2021-0222
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 7.4
  • AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS v2:

  • Severity: Medium
  • Score: 6.1
  • AV:A/AC:L/Au:N/C:N/I:N/A:C
Software From Fixed in
juniper / junos 14.1x53-d45 14.1x53-d45.x
juniper / junos 14.1x53-d35 14.1x53-d35.x
juniper / junos 14.1x53-d10 14.1x53-d10.x
juniper / junos 14.1x53-d40 14.1x53-d40.x
juniper / junos 14.1x53-d30 14.1x53-d30.x
juniper / junos 14.1x53-d42 14.1x53-d42.x
juniper / junos 14.1x53-d25 14.1x53-d25.x
juniper / junos 14.1x53-d27 14.1x53-d27.x
juniper / junos 14.1x53-d16 14.1x53-d16.x
juniper / junos 14.1x53-d15 14.1x53-d15.x
juniper / junos 14.1x53-d43 14.1x53-d43.x
juniper / junos 14.1x53-d44 14.1x53-d44.x
juniper / junos 14.1x53-d26 14.1x53-d26.x
juniper / junos 14.1x53-d50 14.1x53-d50.x
juniper / junos 14.1x53-d34 14.1x53-d34.x
juniper / junos 14.1x53-d48 14.1x53-d48.x
juniper / junos 14.1x53 14.1x53.x
juniper / junos 14.1x53-d51 14.1x53-d51.x
juniper / junos 14.1x53-d52 14.1x53-d52.x
juniper / junos 15.1-r7-s4 15.1-r7-s4.x
juniper / junos 15.1-r7-s5 15.1-r7-s5.x
juniper / junos 15.1-f6-s12 15.1-f6-s12.x
juniper / junos 15.1-r7-s1 15.1-r7-s1.x
juniper / junos 15.1-r7-s2 15.1-r7-s2.x
juniper / junos 15.1-r7-s3 15.1-r7-s3.x
juniper / junos 15.1-f6-s2 15.1-f6-s2.x
juniper / junos 15.1-f6-s1 15.1-f6-s1.x
juniper / junos 15.1 15.1.x
juniper / junos 15.1-r4-s9 15.1-r4-s9.x
juniper / junos 15.1-r6-s6 15.1-r6-s6.x
juniper / junos 15.1-f 15.1-f.x
juniper / junos 15.1-f6-s3 15.1-f6-s3.x
juniper / junos 15.1-r5-s6 15.1-r5-s6.x
juniper / junos 15.1-r6-s2 15.1-r6-s2.x
juniper / junos 15.1-r5 15.1-r5.x
juniper / junos 15.1-r1 15.1-r1.x
juniper / junos 15.1-f2-s1 15.1-f2-s1.x
juniper / junos 15.1-r5-s1 15.1-r5-s1.x
juniper / junos 15.1-f5 15.1-f5.x
juniper / junos 15.1-r6-s1 15.1-r6-s1.x
juniper / junos 15.1-f2-s3 15.1-f2-s3.x
juniper / junos 15.1-f7 15.1-f7.x
juniper / junos 15.1-r4-s7 15.1-r4-s7.x
juniper / junos 15.1-r4-s8 15.1-r4-s8.x
juniper / junos 15.1-r5-s5 15.1-r5-s5.x
juniper / junos 15.1-a1 15.1-a1.x
juniper / junos 15.1-f3 15.1-f3.x
juniper / junos 15.1-r2 15.1-r2.x
juniper / junos 15.1-f5-s7 15.1-f5-s7.x
juniper / junos 15.1-f6-s7 15.1-f6-s7.x
juniper / junos 15.1-f6 15.1-f6.x
juniper / junos 15.1-f2 15.1-f2.x
juniper / junos 15.1-f2-s2 15.1-f2-s2.x
juniper / junos 15.1-r6 15.1-r6.x
juniper / junos 15.1-f4 15.1-f4.x
juniper / junos 15.1-r4 15.1-r4.x
juniper / junos 15.1-f2-s4 15.1-f2-s4.x
juniper / junos 15.1-r3 15.1-r3.x
juniper / junos 15.1-f6-s4 15.1-f6-s4.x
juniper / junos 15.1-r7 15.1-r7.x
juniper / junos 15.1-f1 15.1-f1.x
juniper / junos 16.1-r1 16.1-r1.x
juniper / junos 16.1-r4-s4 16.1-r4-s4.x
juniper / junos 16.1-r4 16.1-r4.x
juniper / junos 16.1-r3 16.1-r3.x
juniper / junos 16.1-r5 16.1-r5.x
juniper / junos 16.1-r2 16.1-r2.x
juniper / junos 16.1-r5-s4 16.1-r5-s4.x
juniper / junos 16.1-r6-s1 16.1-r6-s1.x
juniper / junos 16.1-r7 16.1-r7.x
juniper / junos 16.1-r6-s6 16.1-r6-s6.x
juniper / junos 16.1-r3-s10 16.1-r3-s10.x
juniper / junos 16.1 16.1.x
juniper / junos 16.1-r4-s3 16.1-r4-s3.x
juniper / junos 16.1-r3-s11 16.1-r3-s11.x
juniper / junos 16.1-r7-s3 16.1-r7-s3.x
juniper / junos 16.1-r7-s4 16.1-r7-s4.x
juniper / junos 16.1-r7-s2 16.1-r7-s2.x
juniper / junos 16.1-r7-s5 16.1-r7-s5.x
juniper / junos 16.1-r4-s12 16.1-r4-s12.x
juniper / junos 16.1-r4-s6 16.1-r4-s6.x
juniper / junos 16.1-r4-s2 16.1-r4-s2.x
juniper / junos 16.1-r7-s6 16.1-r7-s6.x
juniper / junos 17.1-r2-s8 17.1-r2-s8.x
juniper / junos 17.1-r2 17.1-r2.x
juniper / junos 17.1 17.1.x
juniper / junos 17.1-r2-s9 17.1-r2-s9.x
juniper / junos 17.1-r2-s10 17.1-r2-s10.x
juniper / junos 17.1-r2-s1 17.1-r2-s1.x
juniper / junos 17.1-r2-s2 17.1-r2-s2.x
juniper / junos 17.1-r2-s3 17.1-r2-s3.x
juniper / junos 17.1-r2-s4 17.1-r2-s4.x
juniper / junos 17.1-r2-s5 17.1-r2-s5.x
juniper / junos 17.1-r2-s6 17.1-r2-s6.x
juniper / junos 17.1-r2-s7 17.1-r2-s7.x
juniper / junos 17.1-r1 17.1-r1.x
juniper / junos 17.1-r3 17.1-r3.x
juniper / junos 17.1-r3-s1 17.1-r3-s1.x
juniper / junos 17.2-r1 17.2-r1.x
juniper / junos 17.2-r1-s2 17.2-r1-s2.x
juniper / junos 17.2-r1-s4 17.2-r1-s4.x
juniper / junos 17.2 17.2.x
juniper / junos 17.2-r1-s7 17.2-r1-s7.x
juniper / junos 17.2-r1-s1 17.2-r1-s1.x
juniper / junos 17.2-r1-s3 17.2-r1-s3.x
juniper / junos 17.2-r1-s5 17.2-r1-s5.x
juniper / junos 17.2-r1-s8 17.2-r1-s8.x
juniper / junos 18.2-r1 18.2-r1.x
juniper / junos 18.2-r2-s3 18.2-r2-s3.x
juniper / junos 18.2-r2-s4 18.2-r2-s4.x
juniper / junos 18.2-r1-s4 18.2-r1-s4.x
juniper / junos 18.2-r1-s5 18.2-r1-s5.x
juniper / junos 18.2-r2 18.2-r2.x
juniper / junos 18.2-r2-s5 18.2-r2-s5.x
juniper / junos 18.2-r2-s6 18.2-r2-s6.x
juniper / junos 18.2 18.2.x
juniper / junos 18.2-r2-s1 18.2-r2-s1.x
juniper / junos 18.2-r2-s2 18.2-r2-s2.x
juniper / junos 18.2-r1-s3 18.2-r1-s3.x
juniper / junos 18.3-r1-s2 18.3-r1-s2.x
juniper / junos 18.3 18.3.x
juniper / junos 18.3-r2 18.3-r2.x
juniper / junos 18.3-r1 18.3-r1.x
juniper / junos 18.3-r1-s1 18.3-r1-s1.x
juniper / junos 18.3-r1-s5 18.3-r1-s5.x
juniper / junos 18.3-r2-s1 18.3-r2-s1.x
juniper / junos 18.3-r2-s2 18.3-r2-s2.x
juniper / junos 18.3-r1-s3 18.3-r1-s3.x
juniper / junos 18.3-r1-s6 18.3-r1-s6.x
juniper / junos 19.2 19.2.x
juniper / junos 19.2-r1-s3 19.2-r1-s3.x
juniper / junos 19.2-r1 19.2-r1.x
juniper / junos 19.2-r1-s1 19.2-r1-s1.x
juniper / junos 19.2-r1-s2 19.2-r1-s2.x
juniper / junos 19.3 19.3.x
juniper / junos 19.3-r1 19.3-r1.x
juniper / junos 19.3-r2 19.3-r2.x
juniper / junos 19.3-r1-s1 19.3-r1-s1.x
juniper / junos 17.2-r2 17.2-r2.x
juniper / junos 17.2-r2-s6 17.2-r2-s6.x
juniper / junos 17.2-r2-s7 17.2-r2-s7.x
juniper / junos 17.2-r3-s1 17.2-r3-s1.x
juniper / junos 17.2-r3-s2 17.2-r3-s2.x
juniper / junos 17.2-r2-s11 17.2-r2-s11.x
juniper / junos 17.3-r2-s2 17.3-r2-s2.x
juniper / junos 17.3 17.3.x
juniper / junos 17.3-r1-s1 17.3-r1-s1.x
juniper / junos 17.3-r2-s4 17.3-r2-s4.x
juniper / junos 17.3-r3-s6 17.3-r3-s6.x
juniper / junos 17.3-r2-s3 17.3-r2-s3.x
juniper / junos 17.3-r3 17.3-r3.x
juniper / junos 17.3-r3-s3 17.3-r3-s3.x
juniper / junos 17.3-r3-s4 17.3-r3-s4.x
juniper / junos 17.3-r3-s5 17.3-r3-s5.x
juniper / junos 17.3-r2-s1 17.3-r2-s1.x
juniper / junos 17.3-r3-s1 17.3-r3-s1.x
juniper / junos 17.3-r3-s2 17.3-r3-s2.x
juniper / junos 17.3-r2 17.3-r2.x
juniper / junos 17.4-r1 17.4-r1.x
juniper / junos 17.4-r2 17.4-r2.x
juniper / junos 17.4-r1-s1 17.4-r1-s1.x
juniper / junos 17.4-r1-s2 17.4-r1-s2.x
juniper / junos 17.4-r2-s1 17.4-r2-s1.x
juniper / junos 17.4 17.4.x
juniper / junos 17.4-r2-s2 17.4-r2-s2.x
juniper / junos 17.4-r2-s3 17.4-r2-s3.x
juniper / junos 17.4-r2-s4 17.4-r2-s4.x
juniper / junos 17.4-r1-s6 17.4-r1-s6.x
juniper / junos 17.4-r1-s7 17.4-r1-s7.x
juniper / junos 17.4-r1-s4 17.4-r1-s4.x
juniper / junos 17.4-r2-s5 17.4-r2-s5.x
juniper / junos 17.4-r2-s6 17.4-r2-s6.x
juniper / junos 17.4-r2-s7 17.4-r2-s7.x
juniper / junos 17.4-r2-s8 17.4-r2-s8.x
juniper / junos 17.4-r1-s5 17.4-r1-s5.x
juniper / junos 18.1-r1 18.1-r1.x
juniper / junos 18.1-r3 18.1-r3.x
juniper / junos 18.1-r2 18.1-r2.x
juniper / junos 18.1-r2-s2 18.1-r2-s2.x
juniper / junos 18.1-r3-s4 18.1-r3-s4.x
juniper / junos 18.1-r3-s3 18.1-r3-s3.x
juniper / junos 18.1-r3-s2 18.1-r3-s2.x
juniper / junos 18.1 18.1.x
juniper / junos 18.1-r2-s1 18.1-r2-s1.x
juniper / junos 18.1-r2-s4 18.1-r2-s4.x
juniper / junos 18.1-r3-s1 18.1-r3-s1.x
juniper / junos 18.1-r3-s6 18.1-r3-s6.x
juniper / junos 18.1-r3-s7 18.1-r3-s7.x
juniper / junos 18.1-r3-s8 18.1-r3-s8.x
juniper / junos 18.2-r3-s1 18.2-r3-s1.x
juniper / junos 18.2-r3-s2 18.2-r3-s2.x
juniper / junos 18.2-r3 18.2-r3.x
juniper / junos 18.3-r1-s4 18.3-r1-s4.x
juniper / junos 18.3-r3 18.3-r3.x
juniper / junos 18.4-r2-s1 18.4-r2-s1.x
juniper / junos 18.4-r2-s2 18.4-r2-s2.x
juniper / junos 18.4-r1 18.4-r1.x
juniper / junos 18.4-r2 18.4-r2.x
juniper / junos 18.4-r1-s3 18.4-r1-s3.x
juniper / junos 18.4-r1-s4 18.4-r1-s4.x
juniper / junos 18.4-r1-s2 18.4-r1-s2.x
juniper / junos 18.4 18.4.x
juniper / junos 18.4-r1-s1 18.4-r1-s1.x
juniper / junos 19.1-r1 19.1-r1.x
juniper / junos 19.1 19.1.x
juniper / junos 19.1-r1-s1 19.1-r1-s1.x
juniper / junos 19.1-r1-s3 19.1-r1-s3.x
juniper / junos 19.1-r1-s2 19.1-r1-s2.x
juniper / junos 19.1-r2 19.1-r2.x

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.