CVE intelligence and bounded remediation

CVE-2020-1646 — Juniper Junos security vulnerability

High CVSS 7.5

On Juniper Networks Junos OS and Junos OS Evolved devices, processing a specific UPDATE for an EBGP peer can lead to a routing process daemon (RPD) crash and restart. This issue occurs only when the device is receiving and processing the BGP UPDATE for an EBGP peer. This issue does not occur when the device is receiving and processing the BGP UPDATE for an IBGP peer. However, the offending BGP UPDATE can originally come from an EBGP peer, propagates through the network via IBGP peers without causing crash, then it causes RPD crash when it is processed for a BGP UPDATE towards an EBGP peer. Repeated receipt and processing of the same specific BGP UPDATE can result in an extended Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 17.3R3-S6, 17.4R2-S7, and 18.1R3-S7. Juniper Networks Junos OS Evolved 19.2R2-EVO and later versions, prior to 19.3R1-EVO. Other Junos OS releases are not affected.

Severity
High
CVSS
7.5 (3.1)
Published
2020-07-17
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-159

Affected products

  • juniper / junos / 17.3
  • juniper / junos / 17.4
  • juniper / junos / 18.1
  • juniper / junos_os_evolved / 19.2

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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