Vulnerability identifier: #VU88458

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2024-21610

CWE-ID: CWE-755

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Juniper Junos OS
Operating systems & Components / Operating system

Vendor: Juniper Networks, Inc.

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

The vulnerability exists due to improper handling of exceptional conditions error in the Class of Service daemon (cosd). A remote non-authenticated attacker can cause a limited Denial of Service (DoS).

In a scaled subscriber scenario when specific low privileged commands, received over NETCONF, SSH or telnet, are handled by cosd on behalf of mgd, the respective child management daemon (mgd) processes will get stuck.

In case of (Netconf over) SSH this leads to stuck SSH sessions, so that when the connection-limit for SSH is reached new sessions can't be established anymore.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 20.4R1 - 20.4R3-S8, 21.2R1 - 21.2R3-S6, 21.3R1 - 21.3R3-S4, 21.4R1 - 21.4R3-S4, 22.1R1 - 22.1R3-S3, 22.2R1 - 22.2R3-S2, 22.3R1 - 22.3R3-S1, 22.4R1 - 22.4R2-S2, 22.4R3-S1, 23.2R1-S1, 23.4R1-S1

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External links
http://supportportal.juniper.net/s/article/2024-04-Security-Bulletin-Junos-OS-MX-Series-In-a-scaled-subscriber-scenario-if-CoS-information-is-gathered-mgd-processes-gets-stuck-CVE-2024-21610

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.