CVE-2025-21602

CVE-2025-21602 is a medium-severity vulnerability in Juniper Junos with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-755.

Key facts

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

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
How severe is CVE-2025-21602?
CVE-2025-21602 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-21602 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21602?
CVE-2025-21602 primarily affects Juniper Junos. In total, 169 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21602?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-21602 have an EU (EUVD) identifier?
Yes. CVE-2025-21602 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2567.
When was CVE-2025-21602 published?
CVE-2025-21602 was published on 2025-01-09 and last updated on 2026-06-17.

References

Affected products (169)

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