medium
5.3
Advisory Published
Updated

CVE-2020-1661: Junos OS: jdhcpd process crash when forwarding a malformed DHCP packet.

First published: Wed Oct 14 2020(Updated: )

On Juniper Networks Junos OS devices configured as a DHCP forwarder, the Juniper Networks Dynamic Host Configuration Protocol Daemon (jdhcp) process might crash when receiving a malformed DHCP packet. This issue only affects devices configured as DHCP forwarder with forward-only option, that forward specified DHCP client packets, without creating a new subscriber session. The jdhcpd daemon automatically restarts without intervention, but continuous receipt of the malformed DHCP packet will repeatedly crash jdhcpd, leading to an extended Denial of Service (DoS) condition. This issue can be triggered only by DHCPv4, it cannot be triggered by DHCPv6. This issue affects Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S16; 12.3X48 versions prior to 12.3X48-D105 on SRX Series; 14.1X53 versions prior to 14.1X53-D60 on EX and QFX Series; 15.1 versions prior to 15.1R7-S7; 15.1X49 versions prior to 15.1X49-D221, 15.1X49-D230 on SRX Series; 15.1X53 versions prior to 15.1X53-D593 on EX2300/EX3400; 16.1 versions prior to 16.1R7-S5.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Junos OS Evolved=12.3
Junos OS Evolved=12.3-r1
Junos OS Evolved=12.3-r10
Junos OS Evolved=12.3-r10-s1
Junos OS Evolved=12.3-r10-s2
Junos OS Evolved=12.3-r11
Junos OS Evolved=12.3-r12
Junos OS Evolved=12.3-r12-s1
Junos OS Evolved=12.3-r12-s11
Junos OS Evolved=12.3-r12-s12
Junos OS Evolved=12.3-r12-s13
Junos OS Evolved=12.3-r12-s14
Junos OS Evolved=12.3-r12-s15
Junos OS Evolved=12.3-r12-s3
Junos OS Evolved=12.3-r12-s4
Junos OS Evolved=12.3-r12-s6
Junos OS Evolved=12.3-r12-s8
Junos OS Evolved=12.3-r2
Junos OS Evolved=12.3-r3
Junos OS Evolved=12.3-r4
Junos OS Evolved=12.3-r5
Junos OS Evolved=12.3-r6
Junos OS Evolved=12.3-r7
Junos OS Evolved=12.3-r8
Junos OS Evolved=12.3-r9
Junos OS Evolved=15.1
Junos OS Evolved=15.1-a1
Junos OS Evolved=15.1-f
Junos OS Evolved=15.1-f1
Junos OS Evolved=15.1-f2
Junos OS Evolved=15.1-f2-s1
Junos OS Evolved=15.1-f2-s2
Junos OS Evolved=15.1-f2-s3
Junos OS Evolved=15.1-f2-s4
Junos OS Evolved=15.1-f3
Junos OS Evolved=15.1-f4
Junos OS Evolved=15.1-f5
Junos OS Evolved=15.1-f5-s7
Junos OS Evolved=15.1-f6
Junos OS Evolved=15.1-f6-s1
Junos OS Evolved=15.1-f6-s12
Junos OS Evolved=15.1-f6-s2
Junos OS Evolved=15.1-f6-s3
Junos OS Evolved=15.1-f6-s4
Junos OS Evolved=15.1-f6-s7
Junos OS Evolved=15.1-f7
Junos OS Evolved=15.1-r1
Junos OS Evolved=15.1-r2
Junos OS Evolved=15.1-r3
Junos OS Evolved=15.1-r4
Junos OS Evolved=15.1-r4-s7
Junos OS Evolved=15.1-r4-s8
Junos OS Evolved=15.1-r4-s9
Junos OS Evolved=15.1-r5
Junos OS Evolved=15.1-r5-s1
Junos OS Evolved=15.1-r5-s5
Junos OS Evolved=15.1-r5-s6
Junos OS Evolved=15.1-r6
Junos OS Evolved=15.1-r6-s1
Junos OS Evolved=15.1-r6-s2
Junos OS Evolved=15.1-r6-s6
Junos OS Evolved=15.1-r7
Junos OS Evolved=15.1-r7-s1
Junos OS Evolved=15.1-r7-s2
Junos OS Evolved=15.1-r7-s3
Junos OS Evolved=15.1-r7-s4
Junos OS Evolved=15.1-r7-s5
Junos OS Evolved=15.1-r7-s6
Junos OS Evolved=16.1
Junos OS Evolved=16.1-r1
Junos OS Evolved=16.1-r2
Junos OS Evolved=16.1-r3
Junos OS Evolved=16.1-r3-s10
Junos OS Evolved=16.1-r3-s11
Junos OS Evolved=16.1-r4
Junos OS Evolved=16.1-r4-s12
Junos OS Evolved=16.1-r4-s2
Junos OS Evolved=16.1-r4-s3
Junos OS Evolved=16.1-r4-s4
Junos OS Evolved=16.1-r4-s6
Junos OS Evolved=16.1-r5
Junos OS Evolved=16.1-r5-s4
Junos OS Evolved=16.1-r6-s1
Junos OS Evolved=16.1-r6-s6
Junos OS Evolved=16.1-r7
Junos OS Evolved=16.1-r7-s2
Junos OS Evolved=16.1-r7-s3
Junos OS Evolved=16.1-r7-s4
Junos OS Evolved=12.3x48
Junos OS Evolved=12.3x48-d10
Junos OS Evolved=12.3x48-d100
Junos OS Evolved=12.3x48-d15
Junos OS Evolved=12.3x48-d20
Junos OS Evolved=12.3x48-d25
Junos OS Evolved=12.3x48-d30
Junos OS Evolved=12.3x48-d35
Junos OS Evolved=12.3x48-d40
Junos OS Evolved=12.3x48-d45
Junos OS Evolved=12.3x48-d50
Junos OS Evolved=12.3x48-d51
Junos OS Evolved=12.3x48-d55
Junos OS Evolved=12.3x48-d60
Junos OS Evolved=12.3x48-d65
Junos OS Evolved=12.3x48-d70
Junos OS Evolved=12.3x48-d75
Junos OS Evolved=12.3x48-d80
Junos OS Evolved=12.3x48-d90
Junos OS Evolved=12.3x48-d95
Junos OS Evolved=15.1x49
Junos OS Evolved=15.1x49-d10
Junos OS Evolved=15.1x49-d100
Junos OS Evolved=15.1x49-d110
Junos OS Evolved=15.1x49-d120
Junos OS Evolved=15.1x49-d130
Junos OS Evolved=15.1x49-d140
Junos OS Evolved=15.1x49-d15
Junos OS Evolved=15.1x49-d150
Junos OS Evolved=15.1x49-d160
Junos OS Evolved=15.1x49-d170
Junos OS Evolved=15.1x49-d180
Junos OS Evolved=15.1x49-d190
Junos OS Evolved=15.1x49-d20
Junos OS Evolved=15.1x49-d200
Junos OS Evolved=15.1x49-d210
Junos OS Evolved=15.1x49-d25
Junos OS Evolved=15.1x49-d30
Junos OS Evolved=15.1x49-d35
Junos OS Evolved=15.1x49-d40
Junos OS Evolved=15.1x49-d45
Junos OS Evolved=15.1x49-d50
Junos OS Evolved=15.1x49-d55
Junos OS Evolved=15.1x49-d60
Junos OS Evolved=15.1x49-d65
Junos OS Evolved=15.1x49-d70
Junos OS Evolved=15.1x49-d75
Junos OS Evolved=15.1x49-d80
Junos OS Evolved=15.1x49-d90
Juniper SRX1500
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX345
Juniper SRX380
Juniper SRX4100
Juniper SRX4200
Juniper SRX4600
Juniper SRX5400
Juniper SRX550
Juniper SRX5600
Juniper SRX5800
Junos OS Evolved=15.1x53
Junos OS Evolved=15.1x53-d10
Junos OS Evolved=15.1x53-d20
Junos OS Evolved=15.1x53-d21
Junos OS Evolved=15.1x53-d210
Junos OS Evolved=15.1x53-d230
Junos OS Evolved=15.1x53-d231
Junos OS Evolved=15.1x53-d232
Junos OS Evolved=15.1x53-d233
Junos OS Evolved=15.1x53-d234
Junos OS Evolved=15.1x53-d235
Junos OS Evolved=15.1x53-d236
Junos OS Evolved=15.1x53-d237
Junos OS Evolved=15.1x53-d25
Junos OS Evolved=15.1x53-d30
Junos OS Evolved=15.1x53-d31
Junos OS Evolved=15.1x53-d32
Junos OS Evolved=15.1x53-d33
Junos OS Evolved=15.1x53-d34
Junos OS Evolved=15.1x53-d40
Junos OS Evolved=15.1x53-d45
Junos OS Evolved=15.1x53-d47
Junos OS Evolved=15.1x53-d470
Junos OS Evolved=15.1x53-d48
Junos OS Evolved=15.1x53-d495
Junos OS Evolved=15.1x53-d50
Junos OS Evolved=15.1x53-d51
Junos OS Evolved=15.1x53-d52
Junos OS Evolved=15.1x53-d55
Junos OS Evolved=15.1x53-d56
Junos OS Evolved=15.1x53-d57
Junos OS Evolved=15.1x53-d58
Junos OS Evolved=15.1x53-d59
Junos OS Evolved=15.1x53-d590
Junos OS Evolved=15.1x53-d591
Junos OS Evolved=15.1x53-d592
Junos OS Evolved=15.1x53-d60
Junos OS Evolved=15.1x53-d61
Junos OS Evolved=15.1x53-d62
Junos OS Evolved=15.1x53-d63
Junos OS Evolved=15.1x53-d64
Junos OS Evolved=15.1x53-d65
Junos OS Evolved=15.1x53-d66
Junos OS Evolved=15.1x53-d67
Junos OS Evolved=15.1x53-d68
Junos OS Evolved=15.1x53-d69
Junos OS Evolved=15.1x53-d70
Juniper EX2300-24T
Juniper EX3400
Junos OS Evolved=14.1x53
Junos OS Evolved=14.1x53-d10
Junos OS Evolved=14.1x53-d15
Junos OS Evolved=14.1x53-d16
Junos OS Evolved=14.1x53-d25
Junos OS Evolved=14.1x53-d26
Junos OS Evolved=14.1x53-d27
Junos OS Evolved=14.1x53-d30
Junos OS Evolved=14.1x53-d34
Junos OS Evolved=14.1x53-d35
Junos OS Evolved=14.1x53-d40
Junos OS Evolved=14.1x53-d42
Junos OS Evolved=14.1x53-d43
Junos OS Evolved=14.1x53-d44
Junos OS Evolved=14.1x53-d45
Junos OS Evolved=14.1x53-d48
Junos OS Evolved=14.1x53-d50
Junos OS Evolved=14.1x53-d51
Junos OS Evolved=14.1x53-d52
Junos OS Evolved=14.1x53-d53
Juniper EX2300-C
Juniper EX4300-24T
Juniper EX4600
Juniper EX4650
Juniper EX9200
Juniper EX9250
Juniper QFX10002-60C
Juniper Networks QFX-Series
Juniper Networks QFX-Series
Juniper QFX5100
Juniper QFX5110
Juniper QFX5120
Juniper Networks QFX-Series
Juniper QFX5200-32C
Juniper QFX5210-64C
Juniper QFX5220

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 12.3R12-S16, 12.3X48-D105, 15.1R7-S7, 15.1X49-D221, 15.1X49-D230, 15.1X53-D593, 16.1R7-S5, 16.2R1 and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2020-1661?

    CVE-2020-1661 is rated as high severity due to the potential for denial of service attacks when impacted devices receive malformed DHCP packets.

  • How do I fix CVE-2020-1661?

    To address CVE-2020-1661, ensure that affected Juniper JUNOS OS software is updated to the latest version provided by Juniper Networks.

  • Which devices are affected by CVE-2020-1661?

    CVE-2020-1661 affects Juniper Networks Junos OS devices configured as DHCP forwarders, specifically versions 12.3 and 15.1 among others.

  • What type of attack does CVE-2020-1661 enable?

    CVE-2020-1661 could enable a denial of service attack resulting from the jdhcp process crashing upon receiving malformed DHCP requests.

  • When was CVE-2020-1661 disclosed?

    CVE-2020-1661 was disclosed on June 29, 2020, highlighting its potential impact on network services.

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