CVE intelligence and bounded remediation

CVE-2024-21618 — Juniper Junos security vulnerability

High CVSS 7.1

An Access of Memory Location After End of Buffer vulnerability in the Layer-2 Control Protocols Daemon (l2cpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker to cause Denial of Service (DoS). On all Junos OS and Junos OS Evolved platforms, when LLDP is enabled on a specific interface, and a malformed LLDP packet is received, l2cpd crashes and restarts. 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: Junos OS: * from 21.4 before 21.4R3-S4, * from 22.1 before 22.1R3-S4, * from 22.2 before 22.2R3-S2, * from 22.3 before 22.3R2-S2, 22.3R3-S1, * from 22.4 before 22.4R3, * from 23.2 before 23.2R2. Junos OS Evolved: * from 21.4-EVO before 21.4R3-S5-EVO, * from 22.1-EVO before 22.1R3-S4-EVO, * from 22.2-EVO before 22.2R3-S2-EVO, * from 22.3-EVO before 22.3R2-S2-EVO, 22.3R3-S1-EVO, * from 22.4-EVO before 22.4R3-EVO, * from 23.2-EVO before 23.2R2-EVO. This issue does not affect: * Junos OS versions prior to 21.4R1; * Junos OS Evolved versions prior to 2…

Severity
High
CVSS
7.1 (4.0)
Published
2024-04-12
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-788, CWE-125

Affected products

  • juniper / junos / 21.4
  • juniper / junos / 22.1

Showing 2 representative product identities from 94 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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