CVE detail

CVE-2021-0207 — CVE-2021-0207

Published 2021-01-15 · Modified 2026-06-17 · Vendor juniper · Product junos · Source nvd
HIGH
severity
CVSS-derived band
7.5
CVSS v3
0–10 scale
0.0126
EPSS probability
exploitation probability, 30d
67.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

Description

An improper interpretation conflict of certain data between certain software components within the Juniper Networks Junos OS devices does not allow certain traffic to pass through the device upon receipt from an ingress interface filtering certain specific types of traffic which is then being redirected to an egress interface on a different VLAN. This causes a Denial of Service (DoS) to those clients sending these particular types of traffic. Such traffic being sent by a client may appear genuine, but is non-standard in nature and should be considered as potentially malicious, and can be targeted to the device, or destined through it for the issue to occur. This issues affects IPv4 and IPv6 traffic. An indicator of compromise may be found by checking log files. You may find that traffic on

Remediation

vendor remediation guidance

The following software releases have been updated to resolve this specific issue: 17.3R3-S7, 17.4R2-S11, 17.4R3-S3, 18.1R3-S9, 18.2R3-S3, 18.3R3-S1, 18.4R1-S5, 18.4R2-S3, 18.4R3, 19.1R1-S5, 19.1R2-S1, 19.1R3, 19.2R1-S5, 19.2R2, 19.3R2-S3, 19.3R3, 19.4R1-S2, 19.4R2, 20.1R1 and all subsequent releases.

workarounds

There are no available workarounds for this issue.

ProductVulnerable rangeFixed versionAdvisory
Juniper Networks Junos OS>=17.3<17.3R3-S717.3R3-S7advisory ↗
Juniper Networks Junos OS>=17.4<17.4R2-S11, 17.4R3-S317.4R2-S11, 17.4R3-S3advisory ↗
Juniper Networks Junos OS>=18.1<18.1R3-S918.1R3-S9advisory ↗
Juniper Networks Junos OS>=18.2<18.2R3-S318.2R3-S3advisory ↗
Juniper Networks Junos OS>=18.3<18.3R3-S118.3R3-S1advisory ↗
Juniper Networks Junos OS>=18.4<18.4R1-S5, 18.4R2-S3, 18.4R318.4R1-S5, 18.4R2-S3, 18.4R3advisory ↗
Juniper Networks Junos OS>=19.1<19.1R1-S5, 19.1R2-S1, 19.1R319.1R1-S5, 19.1R2-S1, 19.1R3advisory ↗
Juniper Networks Junos OS>=19.2<19.2R1-S5, 19.2R219.2R1-S5, 19.2R2advisory ↗
Juniper Networks Junos OS>=19.3<19.3R2-S3, 19.3R319.3R2-S3, 19.3R3advisory ↗
Juniper Networks Junos OS>=19.4<19.4R1-S2, 19.4R219.4R1-S2, 19.4R2advisory ↗

References

cvedb.io · NVD · CISA KEV · FIRST EPSS · vendor advisories (CVE Program List v5). Informational only, no warranty — verify every remediation against the vendor advisory before acting on it. This product uses data from the NVD API but is not endorsed or certified by the NVD, CISA, FIRST.org or any vendor named. CVE® is a registered trademark of The MITRE Corporation.