1. Home
  2. CVE Database
  3. CVE-2026-57023
HIGH · 7.5

CVE-2026-57023

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...

Vulnerability Description

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.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
JuniperJunos23.4
JuniperMx-Spc3-
JuniperMx240-
JuniperMx480-
JuniperMx960-
JuniperSrx1500-
JuniperSrx1600-
JuniperSrx2300-
JuniperSrx300-
JuniperSrx320-
JuniperSrx340-
JuniperSrx345-
JuniperSrx380-
JuniperSrx400-
JuniperSrx4100-
JuniperSrx4120-
JuniperSrx4200-
JuniperSrx4300-
JuniperSrx440-
JuniperSrx4600-

Related Weaknesses (CWE)

CWE-1284

References

FAQ

What is CVE-2026-57023?

CVE-2026-57023 is a vulnerability with a CVSS score of 7.5 (HIGH). 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...

How severe is CVE-2026-57023?

CVE-2026-57023 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-57023?

Check the references section above for vendor advisories and patch information. Affected products include: Juniper Junos, Juniper Mx-Spc3, Juniper Mx240, Juniper Mx480, Juniper Mx960.