CVE-2025-52955

CVE-2025-52955 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-131.

Key facts

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.

Frequently asked questions

What is CVE-2025-52955?
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.
How severe is CVE-2025-52955?
CVE-2025-52955 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-2025-52955 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-52955?
CVE-2025-52955 primarily affects Juniper Junos. In total, 87 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-52955?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-52955 have an EU (EUVD) identifier?
Yes. CVE-2025-52955 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-21163.
When was CVE-2025-52955 published?
CVE-2025-52955 was published on 2025-07-11 and last updated on 2026-06-17.

References

Affected products (87)

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