CVE-2025-52947

Junos OS: ACX Series: When 'hot-standby' mode is configured for an L2 circuit, interface flap causes the FEB to crash

Description

An Improper Handling of Exceptional Conditions vulnerability in route processing of Juniper Networks Junos OS on specific end-of-life (EOL) ACX Series platforms allows an attacker to crash the Forwarding Engine Board (FEB) by flapping an interface, leading to a Denial of Service (DoS). On ACX1000, ACX1100, ACX2000, ACX2100, ACX2200, ACX4000, ACX5048, and ACX5096 devices, FEB0 will crash when the primary path port of the L2 circuit IGP (Interior Gateway Protocol) on the local device goes down. This issue is seen only when 'hot-standby' mode is configured for the L2 circuit. This issue affects Junos OS on ACX1000, ACX1100, ACX2000, ACX2100, ACX2200, ACX4000, ACX5048, and ACX5096:  * all versions before 21.2R3-S9.

Remediation

Solution:

  • The following software releases have been updated to resolve this specific issue: 21.2R3-S9. Note: Support for the ACX2k Series ended with Junos OS 21.2.

Workaround:

  • There are no known workarounds for this issue.

Category

7.1
CVSS
Severity: High
CVSS 4.0 •
CVSS 3.1 •
Vendor Advisory juniper.net
Affected: Juniper Networks Junos OS
Published at:
Updated at:

References

Link Tags
https://supportportal.juniper.net/JSA100051 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2025-52947?
CVE-2025-52947 has been scored as a high severity vulnerability.
How to fix CVE-2025-52947?
To fix CVE-2025-52947: The following software releases have been updated to resolve this specific issue: 21.2R3-S9. Note: Support for the ACX2k Series ended with Junos OS 21.2.
Is CVE-2025-52947 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2025-52947 is being actively exploited.
What software or system is affected by CVE-2025-52947?
CVE-2025-52947 affects Juniper Networks Junos OS.
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