CVE-2020-1632Junos OS and Junos OS Evolved: Invalid BGP UPDATE sent to peer device may cause BGP session to terminate.

Description

In a certain condition, receipt of a specific BGP UPDATE message might cause Juniper Networks Junos OS and Junos OS Evolved devices to advertise an invalid BGP UPDATE message to other peers, causing the other peers to terminate the established BGP session, creating a Denial of Service (DoS) condition. For example, Router A sends a specific BGP UPDATE to Router B, causing Router B to send an invalid BGP UPDATE message to Router C, resulting in termination of the BGP session between Router B and Router C. This issue might occur when there is at least a single BGP session established on the device that does not support 4 Byte AS extension (RFC 4893). Repeated receipt of the same BGP UPDATE can result in an extended DoS condition. This issue affects Juniper Networks Junos OS: 16.1 versions prior to 16.1R7-S6; 16.2 versions prior to 16.2R2-S11; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R2-S8, 17.2R3-S3; 17.2X75 versions prior to 17.2X75-D105, 17.2X75-D110, 17.2X75-D44; 17.3 versions prior to 17.3R2-S5, 17.3R3-S7; 17.4 versions prior to 17.4R2-S8, 17.4R3; 18.1 versions prior to 18.1R3-S8; 18.2 versions prior to 18.2R2-S6, 18.2R3-S2; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D51, 18.2X75-D60; 18.3 versions prior to 18.3R1-S6, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R3; 18.4 version 18.4R2 and later versions; 19.1 versions prior to 19.1R1-S3, 19.1R2; 19.2 versions prior to 19.2R1-S2, 19.2R2. This issue does not affect Juniper Networks Junos OS prior to 16.1R1. This issue affects Juniper Networks Junos OS Evolved prior to 19.2R2-EVO.

Timeline

Scores

EPSS (exploitation in 30 days)

1.1% · top 35% of all CVEs (13 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.

Affected products

• Juniper Networks · Junos OS

  • affected 16.1 – < 16.1R7-S6
  • affected 16.2 – < 16.2R2-S11
  • affected 17.1 – < 17.1R2-S11, 17.1R3-S2
  • affected 17.2 – < 17.2R1-S9, 17.2R2-S8, 17.2R3-S3
  • affected 17.2X75 – < 17.2X75-D105, 17.2X75-D110, 17.2X75-D44
  • affected 17.3 – < 17.3R2-S5, 17.3R3-S7
  • affected 17.4 – < 17.4R2-S8, 17.4R3
  • affected 18.1 – < 18.1R3-S8
  • affected 18.2 – < 18.2R2-S6, 18.2R3-S2
  • affected 18.2X75 – < 18.2X75-D12, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D51, 18.2X75-D60
  • affected 18.3 – < 18.3R1-S6, 18.3R2-S3, 18.3R3
  • affected 18.4 – < 18.4R1-S5, 18.4R3
  • affected 19.1 – < 19.1R1-S3, 19.1R2
  • affected 19.2 – < 19.2R1-S2, 19.2R2

• Juniper Networks · Junos OS Evolved

  • affected unspecified – < 19.2R2-EVO

What to do

Solution: Junos OS: 16.1R7-S6, 16.2R2-S11, 17.1R2-S11, 17.1R3-S2, 17.2R1-S9, 17.2R2-S8, 17.2R3-S3, 17.2X75-D105, 17.2X75-D110, 17.2X75-D44, 17.3R2-S5, 17.3R3-S7, 17.4R2-S8, 17.4R3, 18.1R3-S8, 18.2R2-S6, 18.2R3-S2, 18.2X75-D12, 18.2X75-D33, 18.2X75-D411, 18.2X75-D420, 18.2X75-D51, 18.2X75-D60, 18.3R1-S6, 18.3R2-S3, 18.3R3, 18.4R1-S5, 18.4R3, 19.1R1-S3, 19.1R2, 19.2R1-S2, 19.2R2, 19.3R1, and all subsequent releases. Junos OS Evolved: 19.2R2-EVO, 19.3R1-EVO and all subsequent releases.

Workaround: There are no viable workarounds for this issue.

Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2020-12500 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2020-1632](https://cveledger.app/badge/CVE-2020-1632.svg)](https://cveledger.app/cve/CVE-2020-1632)

Record last updated 17 Sept 2024, 00:40 UTC.