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CVE-2021-0211

CRITICAL severity · CVSS 10 · CWE-754
10CVSS CRITICAL

Summary

An improper check for unusual or exceptional conditions in Juniper Networks Junos OS and Junos OS Evolved Routing Protocol Daemon (RPD) service allows an attacker to send a valid BGP FlowSpec message thereby causing an unexpected change in the route advertisements within the BGP FlowSpec domain leading to disruptions in network traffic causing a Denial of Service (DoS) condition. Continued receipt of these update messages will cause a sustained Denial of Service condition. This issue affects Juniper Networks: Junos OS: All versions prior to 17.3R3-S10 with the exceptions of 15.1X49-D240 on SRX Series and 15.1R7-S8 on EX Series; 17.3 versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R2-S12, 17.4R3-S4; 18.1 versions prior to 18.1R3-S12; 18.2 versions prior to 18.2R2-S8, 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R1-S8, 18.4R2-S6, 18.4R3-S6; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3-S3; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R2-S5, 19.3R3-S1; 19.4 versions prior to 19.4R1-S3, 19.4R2-S3, 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S3 20.2R2; 20.3 versions prior to 20.3R1-S1, 20.3R2. Junos OS Evolved: All versions prior to 20.3R1-S1-EVO, 20.3R2-EVO.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactHigh
Availability impactHigh
Exploit probability (EPSS)1%

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Additional information