medium
6.5
CWE
1284
Advisory Published
Updated

CVE-2023-36839: Junos OS and Junos OS Evolved: An l2cpd crash will occur when specific LLDP packets are received

First published: Thu Oct 12 2023(Updated: )

An Improper Validation of Specified Quantity in Input vulnerability in the Layer-2 control protocols daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker who sends specific LLDP packets to cause a Denial of Service(DoS). This issue occurs when specific LLDP packets are received and telemetry polling is being done on the device. The impact of the l2cpd crash is reinitialization of STP protocols (RSTP, MSTP or VSTP), and MVRP and ERP. Also, if any services depend on LLDP state (like PoE or VoIP device recognition), then these will also be affected. This issue affects: Juniper Networks Junos OS * All versions prior to 20.4R3-S8; * 21.1 version 21.1R1 and later versions; * 21.2 versions prior to 21.2R3-S5; * 21.3 versions prior to 21.3R3-S4; * 21.4 versions prior to 21.4R3-S3; * 22.1 versions prior to 22.1R3-S2; * 22.2 versions prior to 22.2R3; * 22.3 versions prior to 22.3R2-S2; * 22.4 versions prior to 22.4R2; Juniper Networks Junos OS Evolved * All versions prior to 20.4R3-S8-EVO; * 21.1 version 21.1R1-EVO and later versions; * 21.2 versions prior to 21.2R3-S5-EVO; * 21.3 versions prior to 21.3R3-S4-EVO; * 21.4 versions prior to 21.4R3-S3-EVO; * 22.1 versions prior to 22.1R3-S2-EVO; * 22.2 versions prior to 22.2R3-EVO; * 22.3 versions prior to 22.3R2-S2-EVO; * 22.4 versions prior to 22.4R1-S1-EVO;

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=21.1-r1
Juniper Junos=21.1-r1-s1
Juniper Junos=21.1-r2
Juniper Junos=21.1-r2-s1
Juniper Junos=21.1-r2-s2
Juniper Junos=21.1-r3
Juniper Junos=21.1-r3-s1
Juniper Junos=21.1-r3-s2
Juniper Junos=21.1-r3-s3
Juniper Junos=21.1-r3-s4
Juniper Junos=21.1-r3-s5
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=21.3
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=21.4
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=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=22.2-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=22.3-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=22.4-r1
Juniper Junos=22.4-r1-s1
Juniper Junos=22.4-r1-s2
Juniper Networks Junos OS<20.4
Juniper Networks Junos OS=20.4
Juniper Networks Junos OS=20.4-r1
Juniper Networks Junos OS=20.4-r1-s1
Juniper Networks Junos OS=20.4-r1-s2
Juniper Networks Junos OS=20.4-r2
Juniper Networks Junos OS=20.4-r2-s1
Juniper Networks Junos OS=20.4-r2-s2
Juniper Networks Junos OS=20.4-r2-s3
Juniper Networks Junos OS=20.4-r3
Juniper Networks Junos OS=20.4-r3-s1
Juniper Networks Junos OS=20.4-r3-s2
Juniper Networks Junos OS=20.4-r3-s3
Juniper Networks Junos OS=20.4-r3-s4
Juniper Networks Junos OS=20.4-r3-s5
Juniper Networks Junos OS=20.4-r3-s6
Juniper Networks Junos OS=20.4-r3-s7
Juniper Networks Junos OS=21.1-r1
Juniper Networks Junos OS=21.1-r1-s1
Juniper Networks Junos OS=21.1-r2
Juniper Networks Junos OS=21.1-r3
Juniper Networks Junos OS=21.1-r3-s1
Juniper Networks Junos OS=21.1-r3-s2
Juniper Networks Junos OS=21.1-r3-s3
Juniper Networks Junos OS=21.2
Juniper Networks Junos OS=21.2-r1
Juniper Networks Junos OS=21.2-r1-s1
Juniper Networks Junos OS=21.2-r1-s2
Juniper Networks Junos OS=21.2-r2
Juniper Networks Junos OS=21.2-r2-s1
Juniper Networks Junos OS=21.2-r2-s2
Juniper Networks Junos OS=21.2-r3
Juniper Networks Junos OS=21.2-r3-s1
Juniper Networks Junos OS=21.2-r3-s2
Juniper Networks Junos OS=21.2-r3-s3
Juniper Networks Junos OS=21.2-r3-s4
Juniper Networks Junos OS=21.3
Juniper Networks Junos OS=21.3-r1
Juniper Networks Junos OS=21.3-r1-s1
Juniper Networks Junos OS=21.3-r2
Juniper Networks Junos OS=21.3-r2-s1
Juniper Networks Junos OS=21.3-r2-s2
Juniper Networks Junos OS=21.3-r3
Juniper Networks Junos OS=21.3-r3-s1
Juniper Networks Junos OS=21.3-r3-s2
Juniper Networks Junos OS=21.3-r3-s3
Juniper Networks Junos OS=21.4
Juniper Networks Junos OS=21.4-r1
Juniper Networks Junos OS=21.4-r1-s1
Juniper Networks Junos OS=21.4-r1-s2
Juniper Networks Junos OS=21.4-r2
Juniper Networks Junos OS=21.4-r2-s1
Juniper Networks Junos OS=21.4-r2-s2
Juniper Networks Junos OS=21.4-r3
Juniper Networks Junos OS=21.4-r3-s1
Juniper Networks Junos OS=21.4-r3-s2
Juniper Networks Junos OS=22.1-r1
Juniper Networks Junos OS=22.1-r1-s1
Juniper Networks Junos OS=22.1-r1-s2
Juniper Networks Junos OS=22.1-r2
Juniper Networks Junos OS=22.1-r2-s1
Juniper Networks Junos OS=22.1-r3
Juniper Networks Junos OS=22.1-r3-s1
Juniper Networks Junos OS=22.2-r1
Juniper Networks Junos OS=22.2-r1-s1
Juniper Networks Junos OS=22.2-r2
Juniper Networks Junos OS=22.2-r2-s1
Juniper Networks Junos OS=22.2-r2-s2
Juniper Networks Junos OS=22.3-r1
Juniper Networks Junos OS=22.3-r1-s1
Juniper Networks Junos OS=22.3-r1-s2
Juniper Networks Junos OS=22.3-r2
Juniper Networks Junos OS=22.3-r2-s1
Juniper Networks Junos OS=22.4-r1

Remedy

The following software releases have been updated to resolve this specific issue: Junos OS: 20.4R3-S8, 21.2R3-S5, 21.3R3-S4, 21.4R3-S3, 22.1R3-S2, 22.2R3, 22.3R2-S2, 22.3R3, 22.4R2, 23.2R1, and all subsequent releases. Junos OS Evolved: 20.4R3-S8-EVO, 21.2R3-S5-EVO, 21.3R3-S4-EVO, 21.4R3-S3-EVO, 22.1R3-S2-EVO, 22.2R3-EVO, 22.3R2-S2-EVO, 22.3R3-EVO, 22.4R1-S1-EVO, 22.4R2-EVO, 23.1R1-EVO, 23.1R2-EVO, 23.2R1-EVO

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2023-36839?

    CVE-2023-36839 has been categorized with a severity that allows unauthenticated attackers to potentially cause a Denial of Service.

  • How can I mitigate CVE-2023-36839?

    Mitigation for CVE-2023-36839 involves updating to the latest patched version of Junos OS or Junos OS Evolved.

  • Which versions are affected by CVE-2023-36839?

    CVE-2023-36839 affects multiple versions of Juniper Networks Junos OS and Junos OS Evolved, primarily those below version 20.4.

  • What kind of attack does CVE-2023-36839 enable?

    CVE-2023-36839 allows an adjacent attacker to send specific LLDP packets to trigger a Denial of Service condition.

  • Is authentication required to exploit CVE-2023-36839?

    No, exploitation of CVE-2023-36839 can occur without authentication.

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