CVE-2026-21918

HIGH EPSS 29.3%
Published Jan 15, 20265mo ago · Modified Jun 17, 20261w ago
8.7 CVSS 4.0
High
Find Similar
Published Jan 15, 2026 5mo ago
Last Modified Jun 17, 2026 1w ago

Description

A Double Free vulnerability in the flow processing daemon (flowd) of Juniper Networks Junos OS on SRX and MX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). On all SRX and MX Series platforms, when during TCP session establishment a specific sequence of packets is encountered a double free happens. This causes flowd to crash and the respective FPC to restart. This issue affects Junos OS on SRX and MX Series: * all versions before 22.4R3-S7, * 23.2 versions before 23.2R2-S3, * 23.4 versions before 23.4R2-S4, * 24.2 versions before 24.2R2.

CVSS Details

Base Score
8.7
Exploitability
—
Impact
—
Vector string
CVSS: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
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
29.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-415

Affected Products 61

VendorProductVersionRange
juniperjunos* <22.4
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos22.4any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.2any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos23.4any
juniperjunos24.2any
juniperjunos24.2any
juniperjunos24.2any
juniperjunos24.2any
junipermx10004*any
junipermx10008*any
junipermx2008*any
junipermx2010*any
junipermx2020*any
junipermx204*any
junipermx240*any
junipermx304*any
junipermx480*any
junipermx960*any
junipersrx1500*any
junipersrx1600*any
junipersrx2300*any
junipersrx300*any
junipersrx320*any
junipersrx340*any
junipersrx345*any
junipersrx380*any
junipersrx4100*any
junipersrx4120*any
junipersrx4200*any
junipersrx4300*any
junipersrx4600*any
junipersrx4700*any
junipersrx5400*any
junipersrx5600*any
junipersrx5800*any

References 2

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.