PT-2026-56977 · Juniper Networks · Junos

Published

2026-07-09

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Updated

2026-07-09

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CVE-2026-57023

CVSS v3.1

7.5

High

VectorAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
An Improper Validation of Specified Quantity in Input vulnerability in the TCP proxy plugin of Juniper Networks Junos OS on MX Series with SPC3, and SRX Series allows an unauthenticated, network-based attacker to cause a complete Denial of Service (DoS).
When TCP proxy is engaged in a flow session, to support ALGs, Advanced Anti-Malware, ICAP or UTM, a TCP packet with specifically malformed TCP header will cause flow processing daemon (flowd) to crash and restart. This causes a complete service outage until the system has automatically recovered.
This issue affects Junos OS on MX with SPC3, and SRX Series: 
  • 23.4 versions before 23.4R2-S7, 
  • 24.2 versions before 24.2R2-S4, 
  • 24.4 versions before 24.4R2-S3,
  • 25.2 versions before 25.2R2.
This issue does not affect releases before 23.4R1.

Fix

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Weakness Enumeration

Related Identifiers

CVE-2026-57023

Affected Products

Junos