Home/CVE/A persistent cross-site scripting (XSS) vulnerability in the captive portal graphical user interface of Juniper Networks
CVE

CVE-2021-31355

A persistent cross-site scripting (XSS) vulnerability in the captive portal graphical user interface of Juniper Networks

A persistent cross-site scripting (XSS) vulnerability in the captive portal graphical user interface of Juniper Networks Junos OS may allow a remote authenticated user to inject web script or HTML and steal sensitive data and credentials from a web administration session, possibly tricking a follow-on administrative user to perform administrative actions on the device. This issue affects Juniper Networks Junos OS: All versions, including the following supported releases: 12.3X48 versions prior to 12.3X48-D105.

15.1X49 versions prior to 15.1X49-D220.

18.3 versions prior to 18.3R3-S5.

18.4 versions prior to 18.4R3-S9.

19.1 versions prior to 19.1R3-S7.

19.2 versions prior to 19.2R3-S3.

19.3 versions prior to 19.3R3-S4.

19.4 versions prior to 19.4R3-S6.

20.1 versions prior to 20.1R3.

20.2 versions prior to 20.2R1-S1, 20.2R2.

20.3 versions prior to 20.3R2.

20.4 versions prior to 20.4R2.

21.1 versions prior to 21.1R2.

HIGH · CVSS 8 EPSS 0.00329
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
▤

Affected Products & Versions

1
juniper junosall versions
▣

Scoring & Timeline

8
HIGH · CVSS v3.1 · sirt@juniper.net
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD19 Oct 2021 · 07:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
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References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://kb.juniper.net/JSA11220PatchVendor Advisory
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