CVE-2025-21602

MEDIUM
Published Jan 9, 2025 Modified Jan 26, 2026 CWE-755

Description

An Improper Handling of Exceptional Conditions vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker sending a specific BGP update packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS). Continuous receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects iBGP and eBGP, and both IPv4 and IPv6 are affected by this vulnerability. This issue affects Junos OS:  * from 21.4 before 21.4R3-S9,  * from 22.2 before 22.2R3-S5,  * from 22.3 before 22.3R3-S4, * from 22.4 before 22.4R3-S5,  * from 23.2 before 23.2R2-S3,  * from 23.4 before 23.4R2-S3,  * from 24.2 before 24.2R1-S2, 24.2R2;  This issue does not affect versions prior to 21.1R1. Junos OS Evolved:  * from 21.4 before 21.4R3-S9-EVO,  * from 22.2 before 22.2R3-S5-EVO,  * from 22.3 before 22.3R3-S4-EVO, * from 22.4 before 22.4R3-S5-EVO,  * from 23.2 before 23.2R2-S3-EVO,  * from 23.4 before 23.4R2-S3-EVO,  * from 24.2 before 24.2R1-S2-EVO, 24.2R2-EVO. This issue does not affect versions prior to 21.1R1-EVO

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CVSS v3.1 Score

6.5
MEDIUM
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-755 CWE-755

Affected Products

Vendor Product
juniper junos
juniper junos
juniper junos
juniper junos
juniper junos
juniper junos
juniper junos
juniper junos
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juniper junos_os_evolved
juniper junos_os_evolved
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References

Frequently Asked Questions

What is CVE-2025-21602? +
An Improper Handling of Exceptional Conditions vulnerability in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker sending a specific BGP update packet to cause rpd to crash and restart, resulting in a Denial of Service (DoS). Continuous receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue affects iBGP and eBGP, and both IPv4 and IPv6 are affected by this vulnerability. This issue affects Junos OS:  * from 21.4 before 21.4R3-S9,  * from 22.2 before 22.2R3-S5,  * from 22.3 before 22.3R3-S4, * from 22.4 before 22.4R3-S5,  * from 23.2 before 23.2R2-S3,  * from 23.4 before 23.4R2-S3,  * from 24.2 before 24.2R1-S2, 24.2R2;  This issue does not affect versions prior to 21.1R1. Junos OS Evolved:  * from 21.4 before 21.4R3-S9-EVO,  * from 22.2 before 22.2R3-S5-EVO,  * from 22.3 before 22.3R3-S4-EVO, * from 22.4 before 22.4R3-S5-EVO,  * from 23.2 before 23.2R2-S3-EVO,  * from 23.4 before 23.4R2-S3-EVO,  * from 24.2 before 24.2R1-S2-EVO, 24.2R2-EVO. This issue does not affect versions prior to 21.1R1-EVO It has a CVSS v3.1 base score of 6.5 (MEDIUM).
How severe is CVE-2025-21602? +
CVE-2025-21602 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2025-21602? +
CVE-2025-21602 affects products from juniper, specifically: junos, junos_os_evolved. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-21602? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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