medium
6.5
CWE
703 755
Advisory Published
Updated

CVE-2023-36842: Junos OS: jdhcpd will hang on receiving a specific DHCP packet

First published: Fri Jan 12 2024(Updated: )

An Improper Check for Unusual or Exceptional Conditions vulnerability in Juniper DHCP Daemon (jdhcpd) of Juniper Networks Junos OS allows an adjacent, unauthenticated attacker to cause the jdhcpd to consume all the CPU cycles resulting in a Denial of Service (DoS). On Junos OS devices with forward-snooped-client configured, if an attacker sends a specific DHCP packet to a non-configured interface, this will cause an infinite loop. The DHCP process will have to be restarted to recover the service. This issue affects: Juniper Networks Junos OS * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3-S4; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S2; * 22.4 versions earlier than 22.4R2-S2, 22.4R3; * 23.2 versions earlier than 23.2R2.

Credit: sirt@juniper.net

Affected SoftwareAffected VersionHow to fix
Juniper JUNOS<20.4
Juniper JUNOS=20.4
Juniper JUNOS=20.4-r1
Juniper JUNOS=20.4-r1-s1
Juniper JUNOS=20.4-r2
Juniper JUNOS=20.4-r2-s1
Juniper JUNOS=20.4-r2-s2
Juniper JUNOS=20.4-r3
Juniper JUNOS=20.4-r3-s1
Juniper JUNOS=20.4-r3-s2
Juniper JUNOS=20.4-r3-s3
Juniper JUNOS=20.4-r3-s4
Juniper JUNOS=20.4-r3-s5
Juniper JUNOS=20.4-r3-s6
Juniper JUNOS=20.4-r3-s7
Juniper JUNOS=20.4-r3-s8
Juniper JUNOS=21.2
Juniper JUNOS=21.2-r1
Juniper JUNOS=21.2-r1-s1
Juniper JUNOS=21.2-r1-s2
Juniper JUNOS=21.2-r2
Juniper JUNOS=21.2-r2-s1
Juniper JUNOS=21.2-r2-s2
Juniper JUNOS=21.2-r3
Juniper JUNOS=21.2-r3-s1
Juniper JUNOS=21.2-r3-s2
Juniper JUNOS=21.2-r3-s3
Juniper JUNOS=21.2-r3-s4
Juniper JUNOS=21.2-r3-s5
Juniper JUNOS=21.2-r3-s6
Juniper JUNOS=21.3
Juniper JUNOS=21.3-r1
Juniper JUNOS=21.3-r1-s1
Juniper JUNOS=21.3-r1-s2
Juniper JUNOS=21.3-r2
Juniper JUNOS=21.3-r2-s1
Juniper JUNOS=21.3-r2-s2
Juniper JUNOS=21.3-r3
Juniper JUNOS=21.3-r3-s1
Juniper JUNOS=21.3-r3-s2
Juniper JUNOS=21.3-r3-s3
Juniper JUNOS=21.3-r3-s4
Juniper JUNOS=21.4
Juniper JUNOS=21.4-r1
Juniper JUNOS=21.4-r1-s1
Juniper JUNOS=21.4-r1-s2
Juniper JUNOS=21.4-r2
Juniper JUNOS=21.4-r2-s1
Juniper JUNOS=21.4-r2-s2
Juniper JUNOS=21.4-r3
Juniper JUNOS=21.4-r3-s1
Juniper JUNOS=21.4-r3-s2
Juniper JUNOS=21.4-r3-s3
Juniper JUNOS=21.4-r3-s4
Juniper JUNOS=22.1
Juniper JUNOS=22.1-r1
Juniper JUNOS=22.1-r1-s1
Juniper JUNOS=22.1-r1-s2
Juniper JUNOS=22.1-r2
Juniper JUNOS=22.1-r2-s1
Juniper JUNOS=22.1-r2-s2
Juniper JUNOS=22.1-r3
Juniper JUNOS=22.1-r3-s1
Juniper JUNOS=22.1-r3-s2
Juniper JUNOS=22.1-r3-s3
Juniper JUNOS=22.2
Juniper JUNOS=22.2-r1
Juniper JUNOS=22.2-r1-s1
Juniper JUNOS=22.2-r1-s2
Juniper JUNOS=22.2-r2
Juniper JUNOS=22.2-r2-s1
Juniper JUNOS=22.2-r2-s2
Juniper JUNOS=22.2-r3
Juniper JUNOS=22.2-r3-s1
Juniper JUNOS=22.2-r3-s2
Juniper JUNOS=22.3
Juniper JUNOS=22.3-r1
Juniper JUNOS=22.3-r1-s1
Juniper JUNOS=22.3-r1-s2
Juniper JUNOS=22.3-r2
Juniper JUNOS=22.3-r2-s1
Juniper JUNOS=22.3-r2-s2
Juniper JUNOS=22.3-r3
Juniper JUNOS=22.3-r3-s1
Juniper JUNOS=22.4
Juniper JUNOS=22.4-r1
Juniper JUNOS=22.4-r1-s1
Juniper JUNOS=22.4-r1-s2
Juniper JUNOS=22.4-r2
Juniper JUNOS=22.4-r2-s1
Juniper JUNOS=23.2-r1
Juniper JUNOS=23.2-r1-s1
Juniper JUNOS=23.2-r1-s2

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S7, 21.3R3-S5, 21.4R3-S5, 22.1R3-S4, 22.2R3-S3, 22.3R3-S2, 22.4R2-S2, 22.4R3, 23.2R1-S2, 23.2R2, 23.4R1, and all subsequent releases.

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-36842?

    CVE-2023-36842 is classified as a high-severity vulnerability leading to Denial of Service (DoS).

  • How do I fix CVE-2023-36842?

    Fixing CVE-2023-36842 involves upgrading affected Junos OS versions to the latest secure release provided by Juniper Networks.

  • Which versions of Junos OS are affected by CVE-2023-36842?

    CVE-2023-36842 affects Junos OS versions up to 20.4 and various versions from 21.2 through 23.2, including specific releases.

  • Can CVE-2023-36842 be exploited remotely?

    Yes, CVE-2023-36842 can be exploited by an adjacent, unauthenticated attacker over the network.

  • What impact does CVE-2023-36842 have on systems?

    CVE-2023-36842 may cause the Juniper DHCP Daemon to consume all CPU cycles, resulting in a Denial of Service on the device.

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