CVE detail

CVE-2021-0278 — CVE-2021-0278

Published 2021-07-15 · Modified 2026-06-17 · Vendor juniper · Product junos · Source nvd
HIGH
severity
CVSS-derived band
8.8
CVSS v3
0–10 scale
0.0092
EPSS probability
exploitation probability, 30d
57.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

Description

An Improper Input Validation vulnerability in J-Web of Juniper Networks Junos OS allows a locally authenticated attacker to escalate their privileges to root over the target device. junos:18.3R3-S5 junos:18.4R3-S9 junos:19.1R3-S6 junos:19.3R2-S6 junos:19.3R3-S3 junos:19.4R1-S4 junos:19.4R3-S4 junos:20.1R2-S2 junos:20.1R3 junos:20.2R3-S1 junos:20.3X75-D20 junos:20.3X75-D30 junos:20.4R2-S1 junos:20.4R3 junos:21.1R1-S1 junos:21.1R2 junos:21.2R1 junos:21.3R1 This issue affects: Juniper Networks Junos OS 19.3 versions 19.3R1 and above prior to 19.3R2-S6, 19.3R3-S3; 19.4 versions prior to 19.4R3-S5; 20.1 versions prior to 20.1R2-S2, 20.1R3-S1; 20.2 versions prior to 20.2R3-S2; 20.3 versions prior to 20.3R3; 20.4 versions prior to 20.4R2-S1, 20.4R3; 21.1 versions prior to 21.1R1-S1, 21.1R2. This

Remediation

vendor remediation guidance

The following software releases have been updated to resolve this specific issue: 19.3R2-S6, 19.3R3-S3, 19.4R3-S5, 20.1R2-S2, 20.1R3-S1, 20.2R3-S2, 20.3R3, 20.4R2-S1, 20.4R3, 21.1R1-S1, 21.1R2, 21.2R1, and all subsequent releases. In addition to the above fixed releases, for the following not-affected releases additional security enhancements were included in Junos OS 18.3R3-S5, 18.4R3-S9, 19.1R3-S6 as a result of resolving this issue.

workarounds

There are no viable workarounds for this issue other than disabling J-Web. To reduce the risk of exploitation of these issues, use access lists or firewall filters to limit access to only trusted administrative networks, hosts and users.

ProductVulnerable rangeFixed versionAdvisory
Juniper Networks Junos OS>=19.3R1<19.3*19.3*advisory ↗
Juniper Networks Junos OS>=19.4<19.4R3-S519.4R3-S5advisory ↗
Juniper Networks Junos OS>=20.1<20.1R2-S2, 20.1R3-S120.1R2-S2, 20.1R3-S1advisory ↗
Juniper Networks Junos OS>=20.2<20.2R3-S220.2R3-S2advisory ↗
Juniper Networks Junos OS>=20.3<20.3R320.3R3advisory ↗
Juniper Networks Junos OS>=20.4<20.4R2-S1, 20.4R320.4R2-S1, 20.4R3advisory ↗
Juniper Networks Junos OS>=21.1<21.1R1-S1, 21.1R221.1R1-S1, 21.1R2advisory ↗

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.