CVE-2020-1651 Junos OS: MX Series: PFE on the line card may crash due to memory leak.
An attacker can crash the packet forwarding engine by sending specific Layer 2 frames, causing a prolonged denial of service on Juniper MX series routers.
- 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-2020-1651?
CVE-2020-1651 is a medium-severity denial of service vulnerability in Juniper Junos, published on 17 Jul 2020. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
On Juniper Networks MX series, receipt of a stream of specific Layer 2 frames may cause a memory leak resulting in the packet forwarding engine (PFE) on the line card to crash and restart, causing traffic interruption. By continuously sending this stream of specific layer 2 frame, an attacker connected to the same broadcast domain can repeatedly crash the PFE, causing a prolonged Denial of Service (DoS). This issue affects Juniper Networks Junos OS on MX Series: 17.2 versions prior to 17.2R3-S4; 17.2X75 versions prior to 17.2X75-D105.19; 17.3 versions prior to 17.3R3-S7; 17.4 versions prior to 17.4R1-S3, 17.4R2; 18.1 versions prior to 18.1R2. This issue does not affect Juniper Networks Junos OS releases prior to 17.2R1.
Which versions are affected by CVE-2020-1651?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2020-1651?
No fix has been published for CVE-2020-1651 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-2020-1651 being exploited?
There is no known exploitation of CVE-2020-1651 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-x7q7-3cr3-m2q3.