CVE-2023-36840 Junos OS and Junos OS Evolved: An rpd crash occurs when a specific L2VPN command is run
A local low-privileged attacker can cause a sustained Denial of Service by triggering a crash in the Routing Protocol Daemon via a specific L2VPN command.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2023-36840?
CVE-2023-36840 is a medium-severity denial of service vulnerability in Juniper Junos, published on 14 Jul 2023. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A Reachable Assertion vulnerability in Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows a locally-based, low-privileged attacker to cause a Denial of Service (DoS).
On all Junos OS and Junos OS Evolved, when a specific L2VPN command is run, RPD will crash and restart. Continued execution of this specific command will create a sustained Denial of Service (DoS) condition.
This issue affects: Juniper Networks Junos OS All versions prior to 19.3R3-S10; 20.1 versions prior to 20.1R3-S4; 20.2 versions prior to 20.2R3-S6; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S5; 21.1 versions prior to 21.1R3-S4; 21.2 versions prior to 21.2R3-S3; 21.3 versions prior to 21.3R3-S2; 21.4 versions prior to 21.4R3; 22.1 versions prior to 22.1R3; 22.2 versions prior to 22.2R2; 22.3 versions prior to 22.3R2;
Juniper Networks Junos OS Evolved All versions prior to 20.4R3-S7-EVO; 21.1 versions prior to 21.1R3-S3-EVO; 21.2 versions prior to 21.2R3-S5-EVO; 21.3 versions prior to 21.3R3-S4-EVO; 21.4 versions prior to 21.4R3-EVO; 22.1 versions prior to 22.1R3-EVO; 22.2 versions prior to 22.2R2-EVO; 22.3 versions prior to 22.3R2-EVO;
Weakness: CWE-617
Which versions are affected by CVE-2023-36840?
It affects 2 products.
Products include Juniper Junos, Juniper Junos Os Evolved.
How do I fix CVE-2023-36840?
No fix has been published for CVE-2023-36840 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-2023-36840 being exploited?
There is no known exploitation of CVE-2023-36840 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-vfwv-m6qg-w443.