CVE intelligence and bounded remediation

CVE-2020-1637 — Juniper Junos security vulnerability

High CVSS 7.2

A vulnerability in Juniper Networks SRX Series device configured as a Junos OS Enforcer device may allow a user to access network resources that are not permitted by a UAC policy. This issue might occur when the IP address range configured in the Infranet Controller (IC) is configured as an IP address range instead of an IP address/netmask. See the Workaround section for more detail. The Junos OS Enforcer CLI settings are disabled by default. This issue affects Juniper Networks Junos OS on SRX Series: 12.3X48 versions prior to 12.3X48-D100; 15.1X49 versions prior to 15.1X49-D210; 17.3 versions prior to 17.3R2-S5, 17.3R3-S8; 17.4 versions prior to 17.4R2-S9, 17.4R3-S1; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S3; 18.3 versions prior to 18.3R1-S7, 18.3R3-S2; 18.4 versions prior to 18.4R1-S6, 18.4R2-S4, 18.4R3-S1; 19.1 versions prior to 19.1R1-S4, 19.1R2-S1, 19.1R3; 19.2 versions prior to 19.2R1-S3, 19.2R2; 19.3 versions prior to 19.3R2-S1, 19.3R3; 19.4 versions prior to 19.4R1-S1, 19.4R2.

Severity
High
CVSS
7.2 (3.1)
Published
2020-04-08
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-288, CWE-287

Affected products

  • juniper / junos / 12.3x48

Showing 1 representative product identities from 142 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Authentication bypass and missing authentication

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

Check exposure

  • Map every affected endpoint and protocol path, including alternate ports, legacy routes, recovery flows, service accounts, and machine-to-machine access.
  • Confirm which deployments enable the affected authentication mode and whether the interface is reachable from untrusted networks.
  • Review session, token, credential, and proxy trust configuration without attempting account takeover.

Remediate safely

  • Apply the supported fix and centralize fail-closed authentication before protected request handling.
  • Remove default or embedded credentials, rotate affected secrets and sessions, and bind authentication decisions to the intended audience and channel.
  • Add negative tests for alternate routes, malformed or absent credentials, recovery flows, and proxy-derived identity.

Authoritative sources

Complete CVE record and remediation plan

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