CyberSecBulletin
CVE-2025-59964NVD status: Analyzed

Junos OS: Use of Uninitialized Resource

Published Updated By the CyberSecBulletin desk

CVE-2025-59964 is a high-severity use of uninitialized resource vulnerability in Junos OS from Juniper Networks, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 24.4R1-S3, 24.4R2 as the first without the flaw, so updating Junos OS to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Junos OS to 24.4R1-S3, 24.4R2 or a later version.
  2. Read the advisory on supportportal.juniper.net for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Juniper NetworksJunos OS24.4 up to, but not including, 24.4R1-S3, 24.4R224.4R1-S3, 24.4R2
Juniper NetworksJunos24.4Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (juniper.net).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (juniper.net)
CVSS 3.17.5HighCNA (juniper.net)

Official description

A Use of Uninitialized Resource vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on SRX4700 devices allows an unauthenticated, network-based attacker to cause a Denial of Service (DoS). When forwarding-options sampling is enabled, receipt of any traffic destined to the Routing Engine (RE) by the PFE line card leads to an FPC crash and restart, resulting in a Denial of Service (DoS). Continued receipt and processing of any traffic leading to the RE by the PFE line card will create a sustained Denial of Service (DoS) condition to the PFE line card. This issue affects Junos OS on SRX4700: * from 24.4 before 24.4R1-S3, 24.4R2 This issue affects IPv4 and IPv6.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Uninitialized Resource

The product uses or accesses a resource that has not been initialized.

How developers prevent this class of flaw

  • Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
  • Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
  • Avoid race conditions (CWE-362) during initialization routines.

More Use of Uninitialized Resource vulnerabilities (CWE-908)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Junos OS

All Junos OS vulnerabilities

Recent Use of Uninitialized Resource vulnerabilities

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