Description
An Improper Resource Locking vulnerability in the clock synchronization daemon (clksyncd) of Juniper Networks Junos OS on MX Series allows a unauthenticated, logically adjacent attacker to cause a Denial-of-Service (DoS).



If a SyncE or PTP upstream node sends a malformed message to an MX device equipped with SCBE3, a false 19.44MHz alarm is generated on the master RE. This leads to persistent RE switchovers and a clksyncd process crash. This issue is outside the attacker's direct control as it's a race condition.

This issue affects Junos OS on MX Series:


* All versions before 23.2R2-S7.7;
* 23.4 versions before 23.4R2-S8.13;
* 24.2 versions before 24.2R2-S5.5;
* 24.4 versions before 24.4R2-S4;
* 25.2 versions before 25.2R2-S1;
* 25.4 versions before 25.4R1-S2.
Published: 2026-10-14
Score: 6 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

Vendor Solution

The following software releases have been updated to resolve this specific issue: Junos OS: 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S4, 25.2R2-S1, 25.4R1-S2, 26.2R1, and all subsequent releases. Note: For Junos OS releases 23.2, 23.4, and 24.2, specific respins have been referenced. Previously published versions of these releases have been rebuilt to resolve the security vulnerabilities identified in this advisory.

Vendor Workaround

There are no known workarounds for this issue.

Tracking

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Advisories

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History

Wed, 14 Oct 2026 16:45:00 +0000

Type Values Removed Values Added
Description An Improper Resource Locking vulnerability in the clock synchronization daemon (clksyncd) of Juniper Networks Junos OS on MX Series allows a unauthenticated, logically adjacent attacker to cause a Denial-of-Service (DoS). If a SyncE or PTP upstream node sends a malformed message to an MX device equipped with SCBE3, a false 19.44MHz alarm is generated on the master RE. This leads to persistent RE switchovers and a clksyncd process crash. This issue is outside the attacker's direct control as it's a race condition. This issue affects Junos OS on MX Series: * All versions before 23.2R2-S7.7; * 23.4 versions before 23.4R2-S8.13; * 24.2 versions before 24.2R2-S5.5; * 24.4 versions before 24.4R2-S4; * 25.2 versions before 25.2R2-S1; * 25.4 versions before 25.4R1-S2.
Title Junos OS: MX Series: Malformed SyncE or PTP clock input causes continuous RE switchover
Weaknesses CWE-413
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 6, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/AU:Y/R:U/RE:M'}

Subscriptions

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cve-icon MITRE

Status: PUBLISHED

Assigner: juniper

Published:

Updated: 2026-10-14T16:26:55.844Z

Reserved: 2026-09-28T17:37:38.548Z

Link: CVE-2026-102080

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses
  • CWE-413

    Improper Resource Locking