CVE-2021-31361
Vulnérabilité moyenne dans Junos OS (Juniper Networks)
Description
An Improper Check for Unusual or Exceptional Conditions vulnerability combined with Improper Handling of Exceptional Conditions in Juniper Networks Junos OS on QFX Series and PTX Series allows an unauthenticated network based attacker to cause increased FPC CPU utilization by sending specific IP packets which are being VXLAN encapsulated leading to a partial Denial of Service (DoS). Continued receipted of these specific traffic will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS on QFX Series: All versions prior to 17.3R3-S11; 17.4 versions prior to 17.4R2-S13, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S7; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S7, 18.4R3-S7; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S4; 19.2 versions prior to 19.2R1-S6, 19.2R3-S2; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R2-S3, 19.4R3-S1; 20.1 versions prior to 20.1R2, 20.1R3; 20.2 versions prior to 20.2R2, 20.2R3; 20.3 versions prior to 20.3R1-S1, 20.3R2. Juniper Networks Junos OS on PTX Series: All versions prior to 18.4R3-S9; 19.1 versions prior to 19.1R3-S6; 19.2 versions prior to 19.2R1-S7, 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R1-S4, 19.4R3-S5; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R3-S1; 20.3 versions prior to 20.3R2-S1, 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2.
Gravité et risque d'exploitation
CVE-2021-31361 obtient un score CVSS de 5.3/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 1.05 %, ce qui la place devant 63.6 % des CVE référencées.
Que faire ?
- Vérifiez si Junos OS (versions 19.2, <17.3R3-S11, <19.1R3-S6, <18.1R3-S12, 19.3, <19.4R2-S3, 19.4R3-S1, 20.1, <19.3R3-S1, <19.2R1-S7, 19.2R3-S3, <19.4R1-S4, 19.4R3-S5, 18.2, <18.4R3-S9, 20.3, <19.1R1-S6, 19.1R2-S2, 19.1R3-S4, <17.4R2-S13, 17.4R3-S4, 18.3, 19.1, <20.1R2-S2, 20.1R3, 20.4, <21.1R1-S1, 21.1R2, 18.1, 17.4, 21.1, 18.4, <19.3R2-S6, 19.3R3-S3, 19.4, <20.4R2-S1, 20.4R3, <20.3R2-S1, 20.3R3, <19.2R1-S6, 19.2R3-S2, <20.2R3-S1, <20.3R1-S1, 20.3R2, <18.2R2-S8, 18.2R3-S7, <20.2R2, 20.2R3, 20.2, <18.3R3-S4, <20.1R2, 20.1R3, <18.4R1-S8, 18.4R2-S7, 18.4R3-S7) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.