CVE-2024-21596 Memory corruption in Junos OS
An unauthenticated attacker can cause a denial of service on the backup Routing Engine by sending a specific BGP UPDATE message to devices with NSR enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2024-21596?
CVE-2024-21596 is a medium-severity memory corruption vulnerability in Juniper Junos, published on 12 Jan 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A Heap-based Buffer Overflow vulnerability in the Routing Protocol Daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, network based attacker to cause a Denial of Service (DoS).
If an attacker sends a specific BGP UPDATE message to the device, this will cause a memory overwrite and therefore an RPD crash and restart in the backup Routing Engine (RE). Continued receipt of these packets will cause a sustained Denial of Service (DoS) condition in the backup RE.
The primary RE is not impacted by this issue and there is no impact on traffic.
This issue only affects devices with NSR enabled.
Note: NSR is not supported on the SRX Series and is therefore not affected by this vulnerability. This issue requires an attacker to have an established BGP session to a system affected by the issue. This issue affects both eBGP and iBGP implementations.
This issue affects:
Juniper Networks Junos OS
* All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3-S4; * 22.2 versions earlier than 22.2R3-S2; * 22.3 versions earlier than 22.3R3-S1; * 22.4 versions earlier than 22.4R2-S2, 22.4R3; * 23.1 versions earlier than 23.1R2; * 23.2 versions earlier than 23.2R1-S2, 23.2R2.
Juniper Networks Junos OS Evolved
* All versions earlier than 21.3R3-S5-EVO; * 21.4-EVO versions earlier than 21.4R3-S5-EVO; * 22.1-EVO versions earlier than 22.1R3-S4-EVO; * 22.2-EVO versions earlier than 22.2R3-S2-EVO; * 22.3-EVO versions later than 22.3R1-EVO; * 22.4-EVO versions earlier than 22.4R2-S2-EVO, 22.4R3-EVO; * 23.1-EVO versions earlier than 23.1R2-EVO; * 23.2-EVO versions earlier than 23.2R1-S2-EVO, 23.2R2-EVO.
Which versions are affected by CVE-2024-21596?
It affects 2 products.
Products include Juniper Junos, Juniper Junos Os Evolved.
How do I fix CVE-2024-21596?
No fix has been published for CVE-2024-21596 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2024-21596 being exploited?
There is no known exploitation of CVE-2024-21596 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-rj2r-9q5p-4c4w.