CVE detail

CVE-2021-0299 — CVE-2021-0299

Published 2021-10-19 · Modified 2026-06-17 · Vendor juniper · Product junos · Source nvd
HIGH
severity
CVSS-derived band
7.5
CVSS v3
0–10 scale
0.0098
EPSS probability
exploitation probability, 30d
59.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

Description

An Improper Handling of Exceptional Conditions vulnerability in the processing of a transit or directly received malformed IPv6 packet in Juniper Networks Junos OS results in a kernel crash, causing the device to restart, leading to a Denial of Service (DoS). Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition. This issue only affects systems with IPv6 configured. Devices with only IPv4 configured are not vulnerable to this issue. This issue affects Juniper Networks Junos OS: 19.4 versions prior to 19.4R3; 20.1 versions prior to 20.1R2; 20.2 versions prior to 20.2R1-S1, 20.2R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.4R1.

Remediation

vendor remediation guidance

The following software releases have been updated to resolve this specific issue: Junos OS 19.4R3, 20.1R2, 20.2R1-S1, 20.2R2, 20.3R1, and all subsequent releases.

workarounds

There are no viable workarounds for this issue.

ProductVulnerable rangeFixed versionAdvisory
Juniper Networks Junos OS>=19.4<19.4R319.4R3advisory ↗
Juniper Networks Junos OS>=20.1<20.1R220.1R2advisory ↗
Juniper Networks Junos OS>=20.2<20.2R1-S1, 20.2R220.2R1-S1, 20.2R2advisory ↗

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.