CVE intelligence and bounded remediation

CVE-2025-30644 — Juniper Junos security vulnerability

High CVSS 7.7

A Heap-based Buffer Overflow vulnerability in the flexible PIC concentrator (FPC) of Juniper Networks Junos OS on EX2300, EX3400, EX4100, EX4300, EX4300MP, EX4400, EX4600, EX4650-48Y, and QFX5k Series allows an attacker to send a specific DHCP packet to the device, leading to an FPC crash and restart, resulting in a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. Under a rare timing scenario outside the attacker's control, memory corruption may be observed when DHCP Option 82 is enabled, leading to an FPC crash and affecting packet forwarding. Due to the nature of the heap-based overflow, exploitation of this vulnerability could also lead to remote code execution within the FPC, resulting in complete control of the vulnerable component. This issue affects Junos OS on EX2300, EX3400, EX4100, EX4300, EX4300MP, EX4400, EX4600, EX4650-48Y, and QFX5k Series: * All versions before 21.4R3-S9, * from 22.2 before 22.2R3-S5, * 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 24.2R2.

Severity
High
CVSS
7.7 (4.0)
Published
2025-04-09
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-122

Affected products

  • juniper / junos
  • juniper / junos / 21.4

Showing 2 representative product identities from 59 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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