#VU85271 Improper validation of syntactic correctness of input in Juniper Junos OS - CVE-2024-21595

Vulnerability identifier: #VU85271

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2024-21595

CWE-ID: CWE-1286

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 a denial of service (DoS) attack.

The vulnerability exists due to improper validation of syntactic correctness of input error in the Packet Forwarding Engine (PFE). A remote non-authenticated attacker can cause a Denial of Service (DoS).

If an attacker sends high rate of specific ICMP traffic to a device with VXLAN configured, this causes a deadlock of the PFE and results in the device becoming unresponsive.

A manual restart will be required to recover the device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 21.4R1-S1 - 21.4R3-S3, 22.1R1-S1 - 22.1R3-S2, 22.2R1-S1 - 22.2R2, 22.3R1-S1 - 22.3R2-S1, 22.4R1-S1 - 22.4R2-S2, 23.1R1-S1 - 23.1R1, 23.2R1-S1 - 23.2R1-S2

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External links
https://supportportal.juniper.net/s/article/2024-01-Security-Bulletin-Junos-OS-EX4100-EX4400-EX4600-and-QFX5000-Series-A-high-rate-of-specific-ICMP-traffic-will-cause-the-PFE-to-hang-CVE-2024-21595

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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.