Authenticated management-session denial via stuck mgd processes
Published Apr 12, 2024 · Updated May 19, 2025
Improper exceptional-condition handling in Junos OS cosd allows remote authenticated users to block management sessions over SSH or telnet. In scaled CoS deployments with thousands of interfaces, cosd mishandles specific low-privilege state-gathering commands for mgd and leaves child mgd processes stuck. Low-privilege NETCONF, SSH, or telnet access is required; repeated stuck sessions can exhaust the connection limit and prevent new management logins.
Summary
What happened
Improper exceptional-condition handling in Junos OS cosd allows remote authenticated users to block management sessions over SSH or telnet. In scaled CoS deployments with thousands of interfaces, cosd mishandles specific low-privilege state-gathering commands for mgd and leaves child mgd processes stuck. Low-privilege NETCONF, SSH, or telnet access is required; repeated stuck sessions can exhaust the connection limit and prevent new management logins.
The record
- CVE
- CVE-2024-21610
- Published
- Apr 12, 2024
- Updated
- May 19, 2025
- Vendor
- Juniper Networks
- Product
- Junos OS
- Classifications
- CWE-755, T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 12, 2024CVE publishedPublication date reported by the CVE source.
- May 19, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <20.4R3-S9
- Affected versionversion=21.2 <21.2R3-S7
- Affected versionversion=21.3 <21.3R3-S5
- Affected versionversion=21.4 <21.4R3-S5
- Affected versionversion=22.1 <22.1R3-S4
- Affected versionversion=22.2 <22.2R3-S3
- Affected versionversion=22.3 <22.3R3-S2
- Affected versionversion=22.4 <22.4R3
- Affected versionversion=23.2 <23.2R1-S2, 23.2R2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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