CVE-2024-39517 Junos OS and Junos OS Evolved: Upon processing specific L2 traffic, rpd can hang in devices with EVPN/VXLAN configured
An unauthenticated adjacent attacker can cause a denial of service by exhausting CPU resources on Juniper devices configured with EVPN/VXLAN.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2024-39517?
CVE-2024-39517 is a high-severity denial of service vulnerability in Juniper Junos, published on 10 Jul 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An Improper Check for Unusual or Exceptional Conditions vulnerability in the Layer 2 Address Learning Daemon (l2ald) on Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker to cause Denial of Service (DoS).
In an EVPN/VXLAN scenario, when a high amount specific Layer 2 packets are processed by the device, it can cause the Routing Protocol Daemon (rpd) to utilize all CPU resources which causes the device to hang. A manual restart of the rpd is required to restore services.
This issue affects both IPv4 and IPv6 implementations. This issue affects Junos OS: All versions earlier than 21.4R3-S7; 22.1 versions earlier than 22.1R3-S5; 22.2 versions earlier than 22.2R3-S3; 22.3 versions earlier than 22.3R3-S3; 22.4 versions earlier than 22.4R3-S2; 23.2 versions earlier than 23.2R2; 23.4 versions earlier than 23.4R1-S1.
Junos OS Evolved: All versions earlier than 21.4R3-S7-EVO; 22.1-EVO versions earlier than 22.1R3-S5-EVO; 22.2-EVO versions earlier than 22.2R3-S3-EVO; 22.3-EVO versions earlier than 22.3R3-S3-EVO; 22.4-EVO versions earlier than 22.4R3-S2-EVO; 23.2-EVO versions earlier than 23.2R2-EVO; 23.4-EVO versions earlier than 23.4R1-S1-EVO, 23.4R2-EVO.
Weakness: CWE-754
Which versions are affected by CVE-2024-39517?
It affects 2 products.
Products include Juniper Junos, Juniper Junos Os Evolved.
How do I fix CVE-2024-39517?
No fix has been published for CVE-2024-39517 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-39517 being exploited?
There is no known exploitation of CVE-2024-39517 in the wild and no public exploit code.
Other vulnerabilities in Juniper Junos
- CVE-2023-36845 Juniper Junos OS EX Series and SRX Series PHP External Variable Modification
- CVE-2020-1631 Juniper Junos OS Path Traversal
- CVE-2025-21590 Juniper Junos OS Improper Isolation or Compartmentalization
- CVE-2023-36851 Juniper Junos OS SRX Series Missing Authentication for Critical Function
- CVE-2023-36844 Juniper Junos OS EX Series PHP External Variable Modification
Sources
Also known as GHSA-fc5c-g544-fmfp.