CVE-2020-1602

Remote code execution via JDHCPD use-after-free

Published Jan 15, 2020 · Updated Sep 16, 2024

Use-after-free in Juniper Networks Junos OS and Junos OS Evolved allows remote attackers to execute code through crafted IPv4 packets. The IPv4 JDHCPD relay path accesses memory after freeing it, although Juniper does not identify the freed object or triggering packet field. Exploitation requires access to the relay-facing network and JDHCPD relay mode; local-server mode is unaffected, and success takes over the daemon process.

CVSS severity7.1
High
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Juniper Networks Junos OS and Junos OS Evolved allows remote attackers to execute code through crafted IPv4 packets. The IPv4 JDHCPD relay path accesses memory after freeing it, although Juniper does not identify the freed object or triggering packet field. Exploitation requires access to the relay-facing network and JDHCPD relay mode; local-server mode is unaffected, and success takes over the daemon process.

The record

CVE
CVE-2020-1602
Published
Jan 15, 2020
Updated
Sep 16, 2024
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-416, T1210
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 15, 2020CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <19.3R1

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=unspecified <19.3R1
Juniper Networks · Junos OSversion=15.1 <15.1R7-S6; version=15.1X49 <15.1X49-D200; version=15.1X53 <15.1X53-D592; version=16.1 <16.1R7-S6; version=16.2 <16.2R2-S11; version=17.1 <17.1R2-S11, 17.1R3-S1; version=17.2 <17.2R2-S8, 17.2R3-S3; version=17.3 <17.3R3-S6; version=17.4 <17.4R2-S7, 17.4R3; version=18.1 <18.1R3-S8; version=18.2 <18.2R3-S2; version=18.2X75 <18.2X75-D60; version=18.3 <18.3R1-S6, 18.3R2-S2, 18.3R3; version=18.4 <18.4R1-S5, 18.4R2-S3, 18.4R3; version=19.1 <19.1R1-S3, 19.1R2; version=19.2 <19.2R1-S3, 19.2R2; version=19.3 <19.3R1, 19.3R2

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
8.3NIST NVDAV:A/AC:L/Au:N/C:C/I:C/A:C
7.1Juniper Networks, Inc.CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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