Juniper Networks Junos OS/Junos OS Evolved Routing Protocol Daemon out-of-bounds

Summaryinfo

A vulnerability marked as problematic has been reported in Juniper Networks Junos OS and Junos OS Evolved. This issue affects some unknown processing of the component Routing Protocol Daemon. The manipulation leads to out-of-bounds. This vulnerability is uniquely identified as CVE-2025-21598. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Juniper Networks Junos OS and Junos OS Evolved (the affected version is unknown). It has been rated as problematic. This issue affects an unknown code of the component Routing Protocol Daemon. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is availability. The summary by CVE is:

An Out-of-bounds Read vulnerability in Juniper Networks Junos OS and Junos OS Evolved's routing protocol daemon (rpd) allows an unauthenticated, network-based attacker to send malformed BGP packets to a device configured with packet receive trace options enabled to crash rpd. This issue affects: Junos OS:  * from 21.2R3-S8 before 21.2R3-S9,  * from 21.4R3-S7 before 21.4R3-S9,  * from 22.2R3-S4 before 22.2R3-S5,  * from 22.3R3-S2 before 22.3R3-S4,  * from 22.4R3 before 22.4R3-S5,  * from 23.2R2 before 23.2R2-S2,  * from 23.4R1 before 23.4R2-S1,  * from 24.2R1 before 24.2R1-S1, 24.2R2. Junos OS Evolved: * from 21.4R3-S7-EVO before 21.4R3-S9-EVO,  * from 22.2R3-S4-EVO before 22.2R3-S5-EVO,  * from 22.3R3-S2-EVO before 22.3R3-S4-EVO,  * from 22.4R3-EVO before 22.4R3-S5-EVO,  * from 23.2R2-EVO before 23.2R2-S2-EVO,  * from 23.4R1-EVO before 23.4R2-S1-EVO,  * from 24.2R1-EVO before 24.2R1-S2-EVO, 24.2R2-EVO. This issue requires a BGP session to be established. This issue can propagate and multiply through multiple ASes until reaching vulnerable devices. This issue affects iBGP and eBGP. This issue affects IPv4 and IPv6. An indicator of compromise may be the presence of malformed update messages in a neighboring AS which is unaffected by this issue: For example, by issuing the command on the neighboring device:  show log messages Reviewing for similar messages from devices within proximity to each other may indicate this malformed packet is propagating:   rpd[<pid>]: Received malformed update from <IP address> (External AS <AS#>) and   rpd[<pid>]: Malformed Attribute

It is possible to read the advisory at supportportal.juniper.net. The identification of this vulnerability is CVE-2025-21598 since 12/26/2024. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 310755 (Juniper Junos OS Vulnerability (JSA92867)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (310755). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• Juniper Networks

Name

• Junos OS
• Junos OS Evolved

License

• commercial

CPE 2.3info

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CPE 2.2info

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Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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