CVE-2025-52955 Memory corruption in Junos OS
An adjacent attacker can cause a routing daemon crash and sustained denial of service by triggering logical interface flaps when jflow/sflow is 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-2025-52955?
CVE-2025-52955 is a high-severity memory corruption vulnerability in Juniper Junos, published on 11 Jul 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An Incorrect Calculation of Buffer Size vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent unauthenticated attacker to cause a memory corruption that leads to a rpd crash.
When the logical interface using a routing instance flaps continuously, specific updates are sent to the jflow/sflow modules. This results in memory corruption, leading to an rpd crash and restart.
Continued receipt of these specific updates will cause a sustained Denial of Service condition.
This issue affects Junos OS:
* All versions before 21.2R3-S9, * All versions of 21.4, * All versions of 22.2, * from 22.4 before 22.4R3-S7, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S4, * from 24.2 before 24.2R2.
Junos OS Evolved:
* All versions of 21.2-EVO, * All versions of 21.4-EVO, * All versions of 22.2-EVO, * from 22.4 before 22.4R3-S7-EVO, * from 23.2 before 23.2R2-S3-EVO, * from 23.4 before 23.4R2-S4-EVO, * from 24.2 before 24.2R2-EVO.
Weakness: CWE-131
Which versions are affected by CVE-2025-52955?
It affects 2 products.
Products include Juniper Junos, Juniper Junos Os Evolved.
How do I fix CVE-2025-52955?
No fix has been published for CVE-2025-52955 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-2025-52955 being exploited?
There is no known exploitation of CVE-2025-52955 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-8g52-rhvw-9278.