CVE-2025-52951 Details
A Protection Mechanism Failure vulnerability in kernel filter processing of Juniper Networks Junos OS allows an attacker sending IPv6 traffic to an interface to effectively bypass any firewall filtering configured on the interface.

Due to an issue with Junos OS kernel filter processing, the 'payload-protocol' match is not being supported, causing any term containing it to accept all packets without taking any other action. In essence, these firewall filter terms were being processed as an 'accept' for all traffic on the interface.

This issue affects Junos OS: 



* all versions before 21.2R3-S9, 
* from 21.4 before 21.4R3-S11, 
* from 22.2 before 22.2R3-S7, 
* from 22.4 before 22.4R3-S7, 
* from 23.2 before 23.2R2-S4, 
* from 23.4 before 23.4R2-S5, 
* from 24.2 before 24.2R2-S1, 
* from 24.4 before 24.4R1-S2, 24.4R2.



This is a more complete fix for previously published CVE-2024-21607 (JSA75748).
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2025-52951
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.04 Probability of exploitation activity being observed over the next 30 days (14th percentile)
CVSS score for CVE-2025-52951
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
5.8 Medium
Products affected by CVE-2025-52951
Junos 21.4
Junos 22.2
Junos 22.4
Junos 23.2
Junos 23.4
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Not available
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CVE-2025-52951 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
NA 5 25.00%
ZM 4 20.00%
CN 2 10.00%
TW 2 10.00%
US 2 10.00%
VE 2 10.00%
KR 1 5.00%
NG 1 5.00%
VN 1 5.00%

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CVE-2025-52951 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 11 91.67%
Technology 1 8.33%

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