CVE-2026-57023
published 2026-07-09CVE-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…
PriorityP348high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.46%
37.1th percentile
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.
Affected
34 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
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CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv4.08.7HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:M/U:X
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GHSA
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
ghsa_unreviewed·2026-07-10
CVE-2026-57023 [HIGH] CWE-1284 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
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.
VulDB
Juniper Junos OS up to 23.4R2-S6/24.2R2-S3/24.4R2-S2/25.2R1 TCP Proxy Plugin flowd quantity input validation
vuldb·2026-07-10·CVSS 7.5
CVE-2026-57023 [HIGH] Juniper Junos OS up to 23.4R2-S6/24.2R2-S3/24.4R2-S2/25.2R1 TCP Proxy Plugin flowd quantity input validation
A vulnerability categorized as critical has been discovered in Juniper Junos OS up to 23.4R2-S6/24.2R2-S3/24.4R2-S2/25.2R1. This vulnerability affects unknown code of the file flowd of the component TCP Proxy Plugin. Such manipulation of the argument quantity leads to improper input validation.
This vulnerability is documented as CVE-2026-57023. The attack can be executed remotely. There is not any exploit available.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-07-09
Published