CVE-2024-21618
Junos OS and Junos OS Evolved: When LLDP is enabled and a malformed LLDP packet is received, l2cpd crashes
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 21.4R1-EVO.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Junos OS and Junos OS Evolved: When LLDP is enabled and a malformed LLDP packet is received, l2cpd crashes
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 21.4R1-EVO.
- Record
CVE-2024-21618- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-788
- Updated
- 2026-11-02
EUVDEUVD-2024-19266
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 21.4R1-EVO.
- Record
EUVD-2024-19266- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6rj9-5jww-q88j
An Access of Memory Location After End of Buffer vulnerability in the Layer-2 Control Protocols...
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 21.4R1-EVO.
- Record
GHSA-6rj9-5jww-q88j- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-125, CWE-788
- Updated
- 2026-11-02
NVD
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 21.4R1-EVO.
- Record
CVE-2024-21618- CVSS 4.0
- 7.1 High
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-788, CWE-125
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-21618 is a high vulnerability (CVSS 7.1) in Juniper Junos, published April 12, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 22nd percentile. No source names a fixed version.