CVE-2021-0243

Summary

CVECVE-2021-0243
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-22 20:15:00 UTC
Updated2021-04-27 17:11:00 UTC
DescriptionImproper Handling of Unexpected Data in the firewall policer of Juniper Networks Junos OS on EX4300 switches allows matching traffic to exceed set policer limits, possibly leading to a limited Denial of Service (DoS) condition. When the firewall policer discard action fails on a Layer 2 port, it will allow traffic to pass even though it exceeds set policer limits. Traffic will not get discarded, and will be forwarded even though a policer discard action is configured. When the issue occurs, traffic is not discarded as desired, which can be observed by comparing the Input bytes with the Output bytes using the following command: user@junos> monitor interface traffic Interface Link Input bytes (bps) Output bytes (bps) ge-0/0/0 Up 37425422 (82616) 37425354 (82616) <<<< egress ge-0/0/1 Up 37425898 (82616) 37425354 (82616) <<<< ingress The expected output, with input and output counters differing, is shown below: Interface Link Input bytes (bps) Output bytes (bps) ge-0/0/0 Up 342420570 (54600) 342422760 (54600) <<<< egress ge-0/0/1 Up 517672120 (84000) 342420570 (54600) <<<< ingress This issue only affects IPv4 policing. IPv6 traffic and firewall policing actions are not affected by this issue. This issue affects Juniper Networks Junos OS on the EX4300: All versions prior to 17.3R3-S10; 17.4 versions prior to 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S6; 18.3 versions prior to 18.3R3-S4; 18.4 versions prior to 18.4R3-S6; 19.1 versions prior to 19.1R3-S3; 19.2 versions prior to 19.2R3-S1; 19.3 versions prior to 19.3R3-S1; 19.4 versions prior to 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R2.

Risk And Classification

Problem Types: NVD-CWE-Other

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Hardware Juniper Ex4300 - All All All
Operating System Juniper Junos 17.3 - All All
Operating System Juniper Junos 17.3 r1 All All
Operating System Juniper Junos 17.3 r1-s1 All All
Operating System Juniper Junos 17.3 r1-s4 All All
Operating System Juniper Junos 17.3 r2 All All
Operating System Juniper Junos 17.3 r2-s1 All All
Operating System Juniper Junos 17.3 r2-s2 All All
Operating System Juniper Junos 17.3 r2-s3 All All
Operating System Juniper Junos 17.3 r2-s4 All All
Operating System Juniper Junos 17.3 r2-s5 All All
Operating System Juniper Junos 17.3 r3 All All
Operating System Juniper Junos 17.3 r3 - All
Operating System Juniper Junos 17.3 r3-s1 All All
Operating System Juniper Junos 17.3 r3-s2 All All
Operating System Juniper Junos 17.3 r3-s3 All All
Operating System Juniper Junos 17.3 r3-s4 All All
Operating System Juniper Junos 17.3 r3-s5 All All
Operating System Juniper Junos 17.3 r3-s6 All All
Operating System Juniper Junos 17.3 r3-s7 All All
Operating System Juniper Junos 17.3 r3-s8 All All
Operating System Juniper Junos 17.3 r3-s9 All All
Operating System Juniper Junos 17.4 - All All
Operating System Juniper Junos 17.4 r1 All All
Operating System Juniper Junos 17.4 r1-s1 All All
Operating System Juniper Junos 17.4 r1-s2 All All
Operating System Juniper Junos 17.4 r1-s3 All All
Operating System Juniper Junos 17.4 r1-s4 All All
Operating System Juniper Junos 17.4 r1-s5 All All
Operating System Juniper Junos 17.4 r1-s6 All All
Operating System Juniper Junos 17.4 r1-s7 All All
Operating System Juniper Junos 17.4 r2 All All
Operating System Juniper Junos 17.4 r2-s1 All All
Operating System Juniper Junos 17.4 r2-s10 All All
Operating System Juniper Junos 17.4 r2-s11 All All
Operating System Juniper Junos 17.4 r2-s12 All All
Operating System Juniper Junos 17.4 r2-s2 All All
Operating System Juniper Junos 17.4 r2-s3 All All
Operating System Juniper Junos 17.4 r2-s4 All All
Operating System Juniper Junos 17.4 r2-s5 All All
Operating System Juniper Junos 17.4 r2-s6 All All
Operating System Juniper Junos 17.4 r2-s7 All All
Operating System Juniper Junos 17.4 r2-s8 All All
Operating System Juniper Junos 17.4 r2-s9 All All
Operating System Juniper Junos 17.4 r3 All All
Operating System Juniper Junos 17.4 r3-s1 All All
Operating System Juniper Junos 17.4 r3-s2 All All
Operating System Juniper Junos 18.1 - All All
Operating System Juniper Junos 18.1 r1 All All
Operating System Juniper Junos 18.1 r2 All All
Operating System Juniper Junos 18.1 r2-s1 All All
Operating System Juniper Junos 18.1 r2-s2 All All
Operating System Juniper Junos 18.1 r2-s4 All All
Operating System Juniper Junos 18.1 r3 All All
Operating System Juniper Junos 18.1 r3-s1 All All
Operating System Juniper Junos 18.1 r3-s10 All All
Operating System Juniper Junos 18.1 r3-s2 All All
Operating System Juniper Junos 18.1 r3-s3 All All
Operating System Juniper Junos 18.1 r3-s4 All All
Operating System Juniper Junos 18.1 r3-s5 All All
Operating System Juniper Junos 18.1 r3-s6 All All
Operating System Juniper Junos 18.1 r3-s7 All All
Operating System Juniper Junos 18.1 r3-s8 All All
Operating System Juniper Junos 18.1 r3-s9 All All
Operating System Juniper Junos 18.2 - All All
Operating System Juniper Junos 18.2 r1 All All
Operating System Juniper Junos 18.2 r1 - All
Operating System Juniper Junos 18.2 r1-s2 All All
Operating System Juniper Junos 18.2 r1-s3 All All
Operating System Juniper Junos 18.2 r1-s4 All All
Operating System Juniper Junos 18.2 r1-s5 All All
Operating System Juniper Junos 18.2 r2 All All
Operating System Juniper Junos 18.2 r2-s1 All All
Operating System Juniper Junos 18.2 r2-s2 All All
Operating System Juniper Junos 18.2 r2-s3 All All
Operating System Juniper Junos 18.2 r2-s4 All All
Operating System Juniper Junos 18.2 r2-s5 All All
Operating System Juniper Junos 18.2 r2-s6 All All
Operating System Juniper Junos 18.2 r2-s7 All All
Operating System Juniper Junos 18.2 r3 All All
Operating System Juniper Junos 18.2 r3-s1 All All
Operating System Juniper Junos 18.2 r3-s2 All All
Operating System Juniper Junos 18.2 r3-s3 All All
Operating System Juniper Junos 18.2 r3-s4 All All
Operating System Juniper Junos 18.2 r3-s5 All All
Operating System Juniper Junos 18.3 - All All
Operating System Juniper Junos 18.3 r1 All All
Operating System Juniper Junos 18.3 r1-s1 All All
Operating System Juniper Junos 18.3 r1-s2 All All
Operating System Juniper Junos 18.3 r1-s3 All All
Operating System Juniper Junos 18.3 r1-s4 All All
Operating System Juniper Junos 18.3 r1-s5 All All
Operating System Juniper Junos 18.3 r1-s6 All All
Operating System Juniper Junos 18.3 r2 All All
Operating System Juniper Junos 18.3 r2-s1 All All
Operating System Juniper Junos 18.3 r2-s2 All All
Operating System Juniper Junos 18.3 r2-s3 All All
Operating System Juniper Junos 18.3 r2-s4 All All
Operating System Juniper Junos 18.3 r3 All All
Operating System Juniper Junos 18.3 r3-s1 All All
Operating System Juniper Junos 18.3 r3-s2 All All
Operating System Juniper Junos 18.3 r3-s3 All All
Operating System Juniper Junos 18.4 - All All
Operating System Juniper Junos 18.4 r1 All All
Operating System Juniper Junos 18.4 r1-s1 All All
Operating System Juniper Junos 18.4 r1-s2 All All
Operating System Juniper Junos 18.4 r1-s3 All All
Operating System Juniper Junos 18.4 r1-s4 All All
Operating System Juniper Junos 18.4 r1-s5 All All
Operating System Juniper Junos 18.4 r1-s6 All All
Operating System Juniper Junos 18.4 r1-s7 All All
Operating System Juniper Junos 18.4 r2 All All
Operating System Juniper Junos 18.4 r2-s1 All All
Operating System Juniper Junos 18.4 r2-s2 All All
Operating System Juniper Junos 18.4 r2-s3 All All
Operating System Juniper Junos 18.4 r2-s4 All All
Operating System Juniper Junos 18.4 r2-s5 All All
Operating System Juniper Junos 18.4 r2-s6 All All
Operating System Juniper Junos 18.4 r3 All All
Operating System Juniper Junos 18.4 r3-s1 All All
Operating System Juniper Junos 18.4 r3-s2 All All
Operating System Juniper Junos 18.4 r3-s3 All All
Operating System Juniper Junos 18.4 r3-s4 All All
Operating System Juniper Junos 18.4 r3-s5 All All
Operating System Juniper Junos 19.1 - All All
Operating System Juniper Junos 19.1 r1 All All
Operating System Juniper Junos 19.1 r1-s1 All All
Operating System Juniper Junos 19.1 r1-s2 All All
Operating System Juniper Junos 19.1 r1-s3 All All
Operating System Juniper Junos 19.1 r1-s4 All All
Operating System Juniper Junos 19.1 r1-s5 All All
Operating System Juniper Junos 19.1 r2 All All
Operating System Juniper Junos 19.1 r2-s1 All All
Operating System Juniper Junos 19.1 r3 All All
Operating System Juniper Junos 19.1 r3-s1 All All
Operating System Juniper Junos 19.1 r3-s2 All All
Operating System Juniper Junos 19.2 - All All
Operating System Juniper Junos 19.2 r1 All All
Operating System Juniper Junos 19.2 r1-s1 All All
Operating System Juniper Junos 19.2 r1-s2 All All
Operating System Juniper Junos 19.2 r1-s3 All All
Operating System Juniper Junos 19.2 r1-s4 All All
Operating System Juniper Junos 19.2 r1-s5 All All
Operating System Juniper Junos 19.2 r2 All All
Operating System Juniper Junos 19.2 r2-s1 All All
Operating System Juniper Junos 19.2 r3 All All
Operating System Juniper Junos 19.2 r3-s1 All All
Operating System Juniper Junos 19.3 - All All
Operating System Juniper Junos 19.3 r1 All All
Operating System Juniper Junos 19.3 r1-s1 All All
Operating System Juniper Junos 19.3 r2 All All
Operating System Juniper Junos 19.3 r2-s1 All All
Operating System Juniper Junos 19.3 r2-s2 All All
Operating System Juniper Junos 19.3 r2-s3 All All
Operating System Juniper Junos 19.3 r2-s4 All All
Operating System Juniper Junos 19.3 r2-s5 All All
Operating System Juniper Junos 19.3 r3 All All
Operating System Juniper Junos 19.4 r1 All All
Operating System Juniper Junos 19.4 r1-s1 All All
Operating System Juniper Junos 19.4 r1-s2 All All
Operating System Juniper Junos 19.4 r2 All All
Operating System Juniper Junos 19.4 r2-s1 All All
Operating System Juniper Junos 19.4 r2-s2 All All
Operating System Juniper Junos 20.1 r1 All All
Operating System Juniper Junos 20.1 r1-s1 All All
Operating System Juniper Junos 20.1 r1-s2 All All
Operating System Juniper Junos 20.1 r1-s3 All All
Operating System Juniper Junos 20.1 r1-s4 All All
Operating System Juniper Junos 20.2 r1 All All
Operating System Juniper Junos 20.2 r1-s1 All All
Operating System Juniper Junos 20.2 r1-s2 All All
Operating System Juniper Junos 20.2 r1-s3 All All

References

ReferenceSourceLinkTags
2021-04 Security Bulletin: Junos OS: EX4300: Stateless firewall policer fails to discard traffic (CVE-2021-0243) - Juniper Networks MISC kb.juniper.net
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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