CVE-2024-21618

CVE-2024-21618 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2024-21618?
CVE-2024-21618 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-21618 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-21618?
CVE-2024-21618 primarily affects Juniper Junos. In total, 94 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-21618?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-21618 have an EU (EUVD) identifier?
Yes. CVE-2024-21618 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-19266.
When was CVE-2024-21618 published?
CVE-2024-21618 was published on 2024-04-12 and last updated on 2026-06-17.

References

Affected products (94)

More vulnerabilities in Juniper Junos

All CVEs affecting Juniper Junos →

Other CWE-125 (Out-of-bounds Read) vulnerabilities

Browse all CWE-125 (Out-of-bounds Read) vulnerabilities →