Denial of service in Junos OS when handling TCP traffic

1) Input validation error

EUVDB-ID: #VU82115

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-36841

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a unauthenticated network-based attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can cause an infinite loop, resulting in a Denial of Service (DoS). An attacker who sends malformed TCP traffic via an interface configured with PPPoE, causes an infinite loop on the respective PFE.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Juniper Junos OS: 20.4 - 22.4R1-S2

CPE2.3

• cpe:2.3:o:juniper_networks:juniper_junos_os:22.3R2-S1:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:22.1R3-S3:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:21.2R3-S5:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:20.4R3-S6:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:21.4R3-S2:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:22.4R1-S2:*:*:*:*:*:*:*
• cpe:2.3:o:juniper_networks:juniper_junos_os:22.2R2-S2:*:*:*:*:*:*:*

External links

http://supportportal.juniper.net/s/article/2023-10-Security-Bulletin-Junos-OS-MX-Series-Receipt-of-malformed-TCP-traffic-will-cause-a-Denial-of-Service-CVE-2023-36841

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.