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CVE-2026-57023

Junos OS: MX with SPC3, SRX Series: A specifically malformed TCP packet causes a flowd crash

Published: Jul 9, 2026Updated: Jul 14, 2026 Sources: CVE List NVDCWE-1284
7.5HIGH
NVD MITRE
EPSS Score
0.3%
Top 74.5%
CISA KEV
Not in KEV
Exploits
0 Known
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-1284

Affected Products

Juniper Networks
commercial·USaka juniper, juniper networks inc.
Junos OS
Networking Infrastructure
junos
Networking Infrastructure

Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
Workaround Available
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References

https://supportportal.juniper.net/JSA110083
supportportal.juniper.net
News mentions
1

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