Description

A Signed to Unsigned Conversion Error vulnerability in the Layer 2 Control Protocol daemon (l2cpd) of Juniper Networks Junos OS and Juniper Networks Junos OS Evolved allows an unauthenticated adjacent attacker sending a specifically malformed LLDP TLV to cause the l2cpd process to crash and restart, causing a Denial of Service (DoS).  Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.

When an LLDP telemetry subscription is active, receipt of a specifically malformed LLDP TLV causes the l2cpd process to crash and restart.

This issue affects:

Junos OS:

* All versions before 21.2R3-S9, 
* from 21.4 before 21.4R3-S10, 
* from 22.2 before 22.2R3-S6, 
* from 22.4 before 22.4R3-S6, 
* from 23.2 before 23.2R2-S3, 
* from 23.4 before 23.4R2-S4, 
* from 24.2 before 24.2R2; 

Junos OS Evolved: 

* All versions before 21.4R3-S10-EVO,
* from 22.2-EVO before 22.2R3-S6-EVO, 
* from 22.4-EVO before 22.4R3-S6-EVO, 
* from 23.2-EVO before 23.2R2-S3-EVO, 
* from 23.4-EVO before 23.4R2-S4-EVO, 
* from 24.2-EVO before 24.2R2-EVO.

Classification

CVE ID: CVE-2025-30646

CVSS Base Severity: MEDIUM

CVSS Base Score: 6.5

CVSS Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Products

Vendor: Juniper Networks, Juniper Networks

Product: Junos OS, Junos OS Evolved

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.02% (probability of being exploited)

EPSS Percentile: 3.29% (scored less or equal to compared to others)

EPSS Date: 2025-04-21 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-30646
https://supportportal.juniper.net/JSA96456

Timeline