CVE detail

CVE-2021-0275 — CVE-2021-0275

Published 2021-04-22 · Modified 2026-06-17 · Vendor juniper · Product junos · Source nvd
HIGH
severity
CVSS-derived band
8.8
CVSS v3
0–10 scale
0.0117
EPSS probability
exploitation probability, 30d
65.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

Description

A Cross-site Scripting (XSS) vulnerability in J-Web on Juniper Networks Junos OS allows an attacker to target another user's session thereby gaining access to the users session. The other user session must be active for the attack to succeed. Once successful, the attacker has the same privileges as the user. If the user has root privileges, the attacker may be able to gain full control of the device. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15 on EX Series; 12.3X48 versions prior to 12.3X48-D95 on SRX Series; 15.1 versions prior to 15.1R7-S6 on EX Series; 15.1X49 versions prior to 15.1X49-D200 on SRX Series; 16.1 versions prior to 16.1R7-S7; 16.2 versions prior to 16.2R2-S11, 16.2R3; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to

Remediation

vendor remediation guidance

The following software releases have been updated to resolve this specific issue: Junos OS 12.3R12-S15, 12.3X48-D95, 15.1R7-S6, 15.1X49-D200, 16.1R7-S7, 16.2R2-S11, 16.2R3, 17.1R2-S11, 17.1R3-S2, 17.2R3-S3, 17.3R2-S5, 17.3R3-S7, 17.4R2-S9, 17.4R3, 18.1R3-S9, 18.2R2-S7, 18.2R3-S3, 18.3R1-S7, 18.3R2-S3, 18.3R3-S1, 18.4R1-S6, 18.4R2-S4, 18.4R3, 19.1R2-S1, 19.1R3, 19.2R1-S3, 19.2R2, 19.3R2, 19.4R1, and all subsequent releases.

workarounds

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

ProductVulnerable rangeFixed versionAdvisory
Juniper Networks Junos OS>=12.3<12.3R12-S1512.3R12-S15advisory ↗
Juniper Networks Junos OS>=12.3X48<12.3X48-D9512.3X48-D95advisory ↗
Juniper Networks Junos OS>=15.1<15.1R7-S615.1R7-S6advisory ↗
Juniper Networks Junos OS>=15.1X49<15.1X49-D20015.1X49-D200advisory ↗
Juniper Networks Junos OS>=16.1<16.1R7-S716.1R7-S7advisory ↗
Juniper Networks Junos OS>=16.2<16.2R2-S11, 16.2R316.2R2-S11, 16.2R3advisory ↗
Juniper Networks Junos OS>=17.1<17.1R2-S11, 17.1R3-S217.1R2-S11, 17.1R3-S2advisory ↗
Juniper Networks Junos OS>=17.2<17.2R3-S317.2R3-S3advisory ↗
Juniper Networks Junos OS>=17.3<17.3R2-S5, 17.3R3-S717.3R2-S5, 17.3R3-S7advisory ↗
Juniper Networks Junos OS>=17.4<17.4R2-S9, 17.4R317.4R2-S9, 17.4R3advisory ↗
Juniper Networks Junos OS>=18.1<18.1R3-S918.1R3-S9advisory ↗
Juniper Networks Junos OS>=18.2<18.2R2-S7, 18.2R3-S318.2R2-S7, 18.2R3-S3advisory ↗
Juniper Networks Junos OS>=18.3<18.3R1-S7, 18.3R2-S3, 18.3R3-S118.3R1-S7, 18.3R2-S3, 18.3R3-S1advisory ↗
Juniper Networks Junos OS>=18.4<18.4R1-S6, 18.4R2-S4, 18.4R318.4R1-S6, 18.4R2-S4, 18.4R3advisory ↗
Juniper Networks Junos OS>=19.1<19.1R2-S1, 19.1R319.1R2-S1, 19.1R3advisory ↗
Juniper Networks Junos OS>=19.2<19.2R1-S3, 19.2R219.2R1-S3, 19.2R2advisory ↗
Juniper Networks Junos OS>=19.3<19.3R219.3R2advisory ↗

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.