FKIE_CVE-2026-21918
Vulnerability from fkie_nvd - Published: 2026-01-15 21:16 - Updated: 2026-06-17 10:19
Severity
Summary
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.
References
| URL | Tags | ||
|---|---|---|---|
| sirt@juniper.net | https://kb.juniper.net/JSA106018 | Vendor Advisory | |
| sirt@juniper.net | https://supportportal.juniper.net/JSA106018 | Vendor Advisory |
Impacted products
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"value": "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.\n\n\n\n\n\nThis issue affects Junos OS on SRX and MX Series:\n\n\n\n * all versions before 22.4R3-S7,\n * 23.2 versions before 23.2R2-S3,\n * 23.4 versions before 23.4R2-S4,\n * 24.2 versions before 24.2R2."
},
{
"lang": "es",
"value": "Una vulnerabilidad de doble liberaci\u00f3n en el demonio de procesamiento de flujo (flowd) de Juniper Networks Junos OS en las series SRX y MX permite a un atacante no autenticado y basado en red causar una Denegaci\u00f3n de Servicio (DoS). En todas las plataformas de las series SRX y MX, cuando durante el establecimiento de una sesi\u00f3n TCP se encuentra una secuencia espec\u00edfica de paquetes, ocurre una doble liberaci\u00f3n. Esto provoca que flowd se bloquee y que el FPC respectivo se reinicie.\n\nEste problema afecta a Junos OS en las series SRX y MX:\n\n * todas las versiones anteriores a 22.4R3-S7,\n * versiones 23.2 anteriores a 23.2R2-S3,\n * versiones 23.4 anteriores a 23.4R2-S4,\n * versiones 24.2 anteriores a 24.2R2."
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"id": "CVE-2026-21918",
"lastModified": "2026-06-17T10:19:09.647",
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| Author | Source | Type | Date | Other |
|---|
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.