CVE-2021-0258
Vulnérabilité moyenne dans Junos OS (Juniper Networks)
Description
A vulnerability in the forwarding of transit TCPv6 packets received on the Ethernet management interface of Juniper Networks Junos OS allows an attacker to trigger a kernel panic, leading to a Denial of Service (DoS). Continued receipt and processing of these transit packets will create a sustained Denial of Service (DoS) condition. This issue only occurs when TCPv6 packets are routed through the management interface. Other transit traffic, and traffic destined to the management interface, are unaffected by this vulnerability. This issue was introduced as part of a TCP Parallelization feature added in Junos OS 17.2, and affects systems with concurrent network stack enabled. This feature is enabled by default, but can be disabled (see WORKAROUND section below). This issue affects Juniper Networks Junos OS: 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S4; 19.1 versions prior to 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S4, 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.
Gravité et risque d'exploitation
CVE-2021-0258 obtient un score CVSS de 5.9/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.65 %, ce qui la place devant 50.0 % des CVE référencées.
Que faire ?
- Vérifiez si Junos OS (versions <18.2R3-S5, 19.2, 19.3, <19.3R2-S4, 19.3R3, 18.2, <17.4R2-S11, 17.4R3-S2, 18.3, 19.1, <19.1R2-S2, 19.1R3, <18.3R2-S4, 18.3R3-S3, 18.1, <17.3R3-S9, 17.4, <18.4R2-S5, 18.4R3-S4, 18.4, <19.2R1-S5, 19.2R2, 17.3, <18.1R3-S11, 19.4, <17.2R1, <19.4R1-S3, 19.4R2, 17.2) 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.
