Juniper Junos OS Evolved prior 22.4R3-EVO/23.2R2-EVO Packet Forwarding Engine unusual condition

Summaryinfo

A vulnerability was found in Juniper Junos OS Evolved and classified as critical. The impacted element is an unknown function of the component Packet Forwarding Engine. Executing a manipulation can lead to unusual condition. This vulnerability is registered as CVE-2025-59958. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Juniper Junos OS Evolved and classified as critical. This vulnerability affects an unknown code of the component Packet Forwarding Engine. The manipulation with an unknown input leads to a unusual condition vulnerability. The CWE definition for the vulnerability is CWE-754. The product does not check or incorrectly checks for unusual or exceptional conditions that are not expected to occur frequently during day to day operation of the product. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An Improper Check for Unusual or Exceptional Conditions vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS Evolved on PTX Series allows an unauthenticated, network-based attacker to cause impact to confidentiality and availability. When an output firewall filter is configured with one or more terms where the action is 'reject', packets matching these terms are erroneously sent to the Routing Engine (RE) and further processed there. Processing of these packets will consume limited RE resources. Also responses from the RE back to the source of this traffic could reveal confidential information about the affected device. This issue only applies to firewall filters applied to WAN or revenue interfaces, so not the mgmt or lo0 interface of the routing-engine, nor any input filters. This issue affects Junos OS Evolved on PTX Series: * all versions before 22.4R3-EVO, * 23.2 versions before 23.2R2-EVO.

The weakness was published by Firewall as JSA103147. The advisory is available at supportportal.juniper.net. This vulnerability was named CVE-2025-59958 since 09/23/2025. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 10/09/2025).

Upgrading to version 22.4R3-EVO or 23.2R2-EVO eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-2238). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Juniper JUNOS

Productinfo

Type

• Router Operating System

Vendor

• Juniper

Name

• Junos OS Evolved

License

• commercial

Website

• Vendor: https://www.juniper.net/

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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