CVE-2024-21601 Junos OS: SRX Series: Due to an error in processing TCP events flowd will crash
An unauthenticated attacker can cause a sustained denial of service on Juniper SRX devices by triggering a race condition in the flow processing daemon.
- 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-2024-21601?
CVE-2024-21601 is a medium-severity 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 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in the Flow-processing Daemon (flowd) of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (Dos).
On SRX Series devices when two different threads try to simultaneously process a queue which is used for TCP events flowd will crash. One of these threads can not be triggered externally, so the exploitation of this race condition is outside the attackers direct control.
Continued exploitation of this issue will lead to a sustained DoS.
This issue affects Juniper Networks Junos OS:
* 21.2 versions earlier than 21.2R3-S5; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S4; * 22.1 versions earlier than 22.1R3-S3; * 22.2 versions earlier than 22.2R3-S1; * 22.3 versions earlier than 22.3R2-S2, 22.3R3; * 22.4 versions earlier than 22.4R2-S1, 22.4R3.
This issue does not affect Juniper Networks Junos OS versions earlier than 21.2R1.
Weakness: CWE-362
Which versions are affected by CVE-2024-21601?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2024-21601?
No fix has been published for CVE-2024-21601 yet. Limit exposure of the affected software until one is available.
Is CVE-2024-21601 being exploited?
There is no known exploitation of CVE-2024-21601 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-5mjf-6gr5-jvh8.