Vulnerability Database

346,508

Total vulnerabilities in the database

CVE-2020-1657 — juniper / junos

Incorrect Behavior Order: Early Amplification

On SRX Series devices, a vulnerability in the key-management-daemon (kmd) daemon of Juniper Networks Junos OS allows an attacker to spoof packets targeted to IPSec peers before a security association (SA) is established thereby causing a failure to set up the IPSec channel. Sustained receipt of these spoofed packets can cause a sustained Denial of Service (DoS) condition. This issue affects IPv4 and IPv6 implementations. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D90; 15.1X49 versions prior to 15.1X49-D190; 17.4 versions prior to 17.4R2-S9, 17.4R3; 18.1 versions prior to 18.1R3-S9; 18.2 versions prior to 18.2R3; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S6, 18.4R2-S3, 18.4R3; 19.1 versions prior to 19.1R1-S4, 19.1R2. This issue does not affect 12.3 or 15.1 releases which are non-SRX Series releases.

  • Published: Oct 16, 2020
  • Updated: Nov 16, 2025
  • CVE: CVE-2020-1657
  • Severity: High
  • Exploit:

CVSS v3:

  • Severity: High
  • Score: 7.5
  • AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS v2:

  • Severity: Medium
  • Score: 5
  • AV:N/AC:L/Au:N/C:N/I:N/A:P

CWEs:

Software From Fixed in
juniper / junos 12.3x48-d10 12.3x48-d10.x
juniper / junos 15.1x49-d110 15.1x49-d110.x
juniper / junos 12.3x48-d15 12.3x48-d15.x
juniper / junos 12.3x48-d35 12.3x48-d35.x
juniper / junos 12.3x48-d50 12.3x48-d50.x
juniper / junos 15.1x49-d100 15.1x49-d100.x
juniper / junos 12.3x48-d30 12.3x48-d30.x
juniper / junos 12.3x48-d25 12.3x48-d25.x
juniper / junos 12.3x48-d45 12.3x48-d45.x
juniper / junos 12.3x48-d55 12.3x48-d55.x
juniper / junos 12.3x48-d20 12.3x48-d20.x
juniper / junos 15.1x49-d10 15.1x49-d10.x
juniper / junos 15.1x49-d15 15.1x49-d15.x
juniper / junos 12.3x48-d40 12.3x48-d40.x
juniper / junos 12.3x48-d60 12.3x48-d60.x
juniper / junos 12.3x48-d65 12.3x48-d65.x
juniper / junos 15.1x49-d120 15.1x49-d120.x
juniper / junos 15.1x49-d130 15.1x49-d130.x
juniper / junos 17.4-r1 17.4-r1.x
juniper / junos 17.4-r2 17.4-r2.x
juniper / junos 12.3x48-d70 12.3x48-d70.x
juniper / junos 15.1x49-d140 15.1x49-d140.x
juniper / junos 18.1-r1 18.1-r1.x
juniper / junos 18.1-r3 18.1-r3.x
juniper / junos 12.3x48-d75 12.3x48-d75.x
juniper / junos 15.1x49-d160 15.1x49-d160.x
juniper / junos 18.1-r2 18.1-r2.x
juniper / junos 18.2-r1 18.2-r1.x
juniper / junos 12.3x48-d51 12.3x48-d51.x
juniper / junos 17.4-r2-s2 17.4-r2-s2.x
juniper / junos 17.4-r1-s1 17.4-r1-s1.x
juniper / junos 12.3x48-d80 12.3x48-d80.x
juniper / junos 15.1x49-d150 15.1x49-d150.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-s1 18.3-r1-s1.x
juniper / junos 17.4-r1-s2 17.4-r1-s2.x
juniper / junos 18.3-r2 18.3-r2.x
juniper / junos 18.3-r1 18.3-r1.x
juniper / junos 17.4-r2-s1 17.4-r2-s1.x
juniper / junos 18.1-r2-s2 18.1-r2-s2.x
juniper / junos 18.4-r1 18.4-r1.x
juniper / junos 17.4 17.4.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 12.3x48 12.3x48.x
juniper / junos 15.1x49 15.1x49.x
juniper / junos 18.3-r1-s2 18.3-r1-s2.x
juniper / junos 18.3 18.3.x
juniper / junos 18.4 18.4.x
juniper / junos 17.4-r1-s5 17.4-r1-s5.x
juniper / junos 18.1-r3-s1 18.1-r3-s1.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 18.4-r1-s1 18.4-r1-s1.x
juniper / junos 15.1x49-d180 15.1x49-d180.x
juniper / junos 15.1x49-d170 15.1x49-d170.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 18.3-r1-s3 18.3-r1-s3.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 18.4-r1-s2 18.4-r1-s2.x
juniper / junos 19.1-r1 19.1-r1.x
juniper / junos 19.1 19.1.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 18.4-r2 18.4-r2.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 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 18.2-r2-s5 18.2-r2-s5.x
juniper / junos 18.2-r2-s6 18.2-r2-s6.x
juniper / junos 18.4-r1-s5 18.4-r1-s5.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 17.4-r2-s8 17.4-r2-s8.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 18.3-r1-s6 18.3-r1-s6.x
juniper / junos 18.1-r3-s8 18.1-r3-s8.x
juniper / junos 17.4-r2-s10 17.4-r2-s10.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.