#VU82091 Improper validation of specified quantity in input in Junos OS Evolved and Juniper Junos OS - CVE-2023-36839

Vulnerability identifier: #VU82091

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:A/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-2023-36839

CWE-ID: N/A

Exploitation vector: Local network

Exploit availability: No

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

Vendor: Juniper Networks, Inc.

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper validation of specified quantity in input in the layer-2 control protocols daemon (l2cpd). A remote attacker on the local network can send specially crafted LLDP packet to the affected device to perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Junos OS Evolved: 20.4R1-EVO, 20.4R1-S1-EVO, 20.4R1-S2-EVO, 20.4R2-EVO, 20.4R2-S1-EVO, 20.4R2-S2-EVO, 20.4R2-S3-EVO, 20.4R3-EVO, 20.4R3-S1-EVO, 20.4R3-S2-EVO, 20.4R3-S3-EVO, 20.4R3-S4-EVO, 20.4R3-S5-EVO, 20.4R3-S6-EVO, 20.4R3-S7-EVO, 20.4, 21.2R1-EVO, 21.2R1-S1-EVO, 21.2R1-S2-EVO, 21.2R2-EVO, 21.2R2-S1-EVO, 21.2R2-S2-EVO, 21.2R3-EVO, 21.2R3-S1-EVO, 21.2R3-S2-EVO, 21.2R3-S3-EVO, 21.2R3-S4-EVO, 21.2-EVO, 21.3R1-EVO, 21.3R1-S1-EVO, 21.3R2-EVO, 21.3R2-S1-EVO, 21.3R2-S2-EVO, 21.3R3-EVO, 21.3R3-S1-EVO, 21.3R3-S2-EVO, 21.3R3-S3-EVO, 21.3-EVO, 21.4R1-EVO, 21.4R1-S1-EVO, 21.4R1-S2-EVO, 21.4R2-EVO, 21.4R2-S1-EVO, 21.4R2-S2-EVO, 21.4R3-EVO, 21.4R3-S1-EVO, 21.4R3-S2-EVO, 22.1R1-EVO, 22.1R1-S1-EVO, 22.1R1-S2-EVO, 22.1R2-EVO, 22.1R2-S1-EVO, 22.1R3-EVO, 22.1R3-S1-EVO, 22.1-EVO, 22.2R1-EVO, 22.2R1-S1-EVO, 22.2R2-EVO, 22.2R2-S1-EVO, 22.2R2-S2-EVO, 22.2-EVO, 22.3R1-EVO, 22.3R1-S1-EVO, 22.3R1-S2-EVO, 22.3R2-EVO, 22.3R2-S1-EVO, 22.4R1-EVO, 23.1R1-S1-EVO

Juniper Junos OS: 20.4R1-S1, 20.4R2-S1, 20.4R2-S2, 20.4R3-S1, 20.4R3-S2, 20.4R3-S3, 20.4R3-S4, 20.4R3-S5, 20.4R3-S6, 20.4R3-S7, 20.4, 20.4R1, 20.4R2, 20.4R3, 21.2R1-S1, 21.2R1-S2, 21.2R2-S1, 21.2R2-S2, 21.2R3-S1, 21.2R3-S2, 21.2R3-S3, 21.2R3-S4, 21.2R1, 21.2R2, 21.2R3, 21.3R1-S1, 21.3R1-S2, 21.3R2-S1, 21.3R2-S2, 21.3R3-S1, 21.3R3-S2, 21.3R3-S3, 21.3R1, 21.3R2, 21.3R3, 21.4R1-S1, 21.4R1-S2, 21.4R2-S1, 21.4R2-S2, 21.4R3-S1, 21.4R3-S2, 21.4R1, 21.4R2, 21.4R3, 22.1R1-S1, 22.1R1-S2, 22.1R2-S1, 22.1R2-S2, 22.1R3-S1, 22.1R1, 22.1R2, 22.1R3, 22.2R1-S1, 22.2R1-S2, 22.2R2-S1, 22.2R2-S2, 22.2R1, 22.2R2, 22.3R1-S1, 22.3R1-S2, 22.3R2-S1, 22.3R1, 22.3R2, 22.4R1-S1, 22.4R1-S2, 22.4R1

---

External links
https://supportportal.juniper.net/s/article/2023-10-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-An-l2cpd-crash-will-occur-when-specific-LLDP-packets-are-received-CVE-2023-36839

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

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