CVE-2021-28162Public exploitNetwork attack vector

Script execution via unescaped notification messages

Published Mar 12, 2021 · Updated Aug 3, 2024

Cross-site scripting in Eclipse Theia 0.16.0 and earlier allows remote attackers to execute JavaScript through crafted notification text. NotificationComponent passes the message string to React's dangerouslySetInnerHTML property without escaping it, placing attacker-supplied markup in the DOM. Exploitation requires user interaction that displays the crafted message; the resulting script runs in the affected application's frontend context.

CVSS severity6.1
Medium
EPSS probability0.78%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Eclipse Theia 0.16.0 and earlier allows remote attackers to execute JavaScript through crafted notification text. NotificationComponent passes the message string to React's dangerouslySetInnerHTML property without escaping it, placing attacker-supplied markup in the DOM. Exploitation requires user interaction that displays the crafted message; the resulting script runs in the affected application's frontend context.

The record

CVE
CVE-2021-28162
Published
Mar 12, 2021
Updated
Aug 3, 2024
Vendor
The Eclipse Foundation
Product
Eclipse Theia
Classifications
CWE-829, CWE-830
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <=0.16.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Eclipse Foundation · Eclipse Theiaversion=unspecified <=0.16.0

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-829Inclusion of Functionality from Untrusted Control Sphere
CWE-830Inclusion of Web Functionality from an Untrusted Source

Public exploit references

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

Technologies

Your stack

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Your stack

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