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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Juniper Networks | Junos OS | < 22.4R3-S7, 23.2 – < 23.2R2-S3, 23.4 – < 23.4R2-S4, 24.2 – < 24.2R2 | 22.4R3-S7 |
Advisories 2
- NCSC-2026-0017 Kwetsbaarheden verholpen in Juniper Networks JunOS NCSC-NL (Netherlands) · Jan 16, 2026
- WID-SEC-2026-0117 Juniper Junos OS, Junos Space: Mehrere Schwachstellen BSI CERT-Bund (WID) · Jan 15, 2026
References
- https://supportportal.juniper.net/JSA106018 vendor-advisory
- https://kb.juniper.net/JSA106018 vendor-advisory