CVE-2024-21593 Junos OS: MX Series with MPC10, MPC11, LC9600, and MX304: A specific MPLS packet will cause a PFE crash
An unauthenticated adjacent attacker can cause a sustained Denial of Service by sending specific MPLS packets to affected Juniper MX routers with CCC configured.
- 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-2024-21593?
CVE-2024-21593 is a high-severity denial of service vulnerability in Juniper Junos, published on 12 Apr 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An Improper Check or Handling of Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker to cause a Denial of Service (DoS).
If an attacker sends a specific MPLS packet, which upon processing, causes an internal loop, that leads to a PFE crash and restart. Continued receipt of these packets leads to a sustained Denial of Service (DoS) condition. Circuit cross-connect (CCC) needs to be configured on the device for it to be affected by this issue.
This issue only affects MX Series with MPC10, MPC11, LC9600, and MX304.
This issue affects: Juniper Networks Junos OS 21.4 versions from 21.4R3 earlier than 21.4R3-S5; 22.2 versions from 22.2R2 earlier than 22.2R3-S2; 22.3 versions from 22.3R1 earlier than 22.3R2-S2; 22.3 versions from 22.3R3 earlier than 22.3R3-S1 22.4 versions from 22.4R1 earlier than 22.4R2-S2, 22.4R3; 23.2 versions earlier than 23.2R1-S1, 23.2R2.
Weakness: CWE-703
Which versions are affected by CVE-2024-21593?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2024-21593?
No fix has been published for CVE-2024-21593 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-2024-21593 being exploited?
There is no known exploitation of CVE-2024-21593 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-chjj-m6f7-j5g6.