CVE-2023-36839

Summary

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;

Affected Software

VendorProductVersion RangeStatus
Juniper NetworksJunos OS0 < 20.4R3-S8affected
Juniper NetworksJunos OS21.1R1 < 21.1*affected
Juniper NetworksJunos OS21.2 < 21.2R3-S5affected
Juniper NetworksJunos OS21.3 < 21.3R3-S4affected
Juniper NetworksJunos OS21.4 < 21.4R3-S3affected
Juniper NetworksJunos OS22.1 < 22.1R3-S2affected
Juniper NetworksJunos OS22.2 < 22.2R3affected
Juniper NetworksJunos OS22.3 < 22.3R2-S2, 22.3R3affected
Juniper NetworksJunos OS22.4 < 22.4R2affected
Juniper NetworksJunos OS Evolved0 < 20.4R3-S8-EVOaffected
Juniper NetworksJunos OS Evolved21.1R1-EVO < 21.1*-EVOaffected
Juniper NetworksJunos OS Evolved21.2-EVO < 21.2R3-S5-EVOaffected
Juniper NetworksJunos OS Evolved21.3-EVO < 21.3R3-S4-EVOaffected
Juniper NetworksJunos OS Evolved21.4-EVO < 21.4R3-S3-EVOaffected
Juniper NetworksJunos OS Evolved22.1-EVO < 22.1R3-S2-EVOaffected
Juniper NetworksJunos OS Evolved22.2-EVO < 22.2R3-EVOaffected
Juniper NetworksJunos OS Evolved22.3-EVO < 22.3R2-S2-EVO, 22.3R3-EVOaffected
Juniper NetworksJunos OS Evolved22.4-EVO < 22.4R1-S1-EVO, 22.4R2-EVOaffected

Weaknesses

  • CWE-1284: CWE-1284: Improper Validation of Specified Quantity in Input
  • Denial of Service (DoS)

Workarounds

If LLDP and its services are not required, customers can disable LLDP. Disabling telemetry polling also mitigates the issue.

There are no other known workarounds for this issue.

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References