CVE-2021-29110Network attack vector

Browser script execution via stored home content

Published Oct 1, 2021 · Updated Apr 10, 2025

Stored XSS in Esri Portal for ArcGIS 10.9 and earlier allows remote unauthenticated attackers to store scripts in the home application. The home application accepts and persists malicious strings without neutralizing script content before later browser rendering. The current CNA description requires no authentication, while Esri's advisory and CVSS assessment require low privileges and user interaction.

CVSS severity5.4
Medium
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stored XSS in Esri Portal for ArcGIS 10.9 and earlier allows remote unauthenticated attackers to store scripts in the home application. The home application accepts and persists malicious strings without neutralizing script content before later browser rendering. The current CNA description requires no authentication, while Esri's advisory and CVSS assessment require low privileges and user interaction.

The record

CVE
CVE-2021-29110
Published
Oct 1, 2021
Updated
Apr 10, 2025
Vendor
Esri
Product
Portal for ArcGIS
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 1, 2021CVE publishedPublication date reported by the CVE source.
  2. Apr 10, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=All <=10.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Esri · Portal for ArcGISversion=All <=10.9

Published CVSS scores

5.4Environmental Systems Research Institute, Inc.CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NISTAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4NISTCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
5.2EsriCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N/RL:O/RC:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo