Out-of-bounds Read in Juniper Junos

CVE-2024-21618

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.

EPSS: 0.003 (21.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2024-21618?
CVE-2024-21618 is a medium-severity vulnerability in Juniper Junos, classified under CWE-788. CVSS score: 6.5/10. Published 2024-04-12.
How severe is CVE-2024-21618?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2024-21618 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.