CVE-2026-35565: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Apache Software Foundation Apache Storm UI
Stored Cross-Site Scripting (XSS) via Unsanitized Topology Metadata in Apache Storm UI Versions Affected: before 2.8.6 Description: The Storm UI visualization component interpolates topology metadata including component IDs, stream names, and grouping values directly into HTML via innerHTML in parseNode() and parseEdge() without sanitization at any layer. An authenticated user with topology submission rights could craft a topology containing malicious HTML/JavaScript in component identifiers (e.g., a bolt ID containing an onerror event handler). This payload flows through Nimbus → Thrift → the Visualization API → vis.js tooltip rendering, resulting in stored cross-site scripting. In multi-tenant deployments where topology submission is available to less-trusted users but the UI is accessed by operators or administrators, this enables privilege escalation through script execution in an admin's browser session. Mitigation: 2.x users should upgrade to 2.8.6. Users who cannot upgrade immediately should monkey-patch the parseNode() and parseEdge() functions in the visualization JavaScript file to HTML-escape all API-supplied values including nodeId, :capacity, :latency, :component, :stream, and :grouping before interpolation into tooltip HTML strings, and should additionally restrict topology submission to trusted users via Nimbus ACLs as a defense-in-depth measure. A guide on how to do this is available in the release notes of 2.8.6. Credit: This issue was discovered while investigating another report by K.
AI Analysis
Technical Summary
Apache Storm UI's visualization component improperly neutralizes input during web page generation by directly interpolating topology metadata into HTML via innerHTML without sanitization. This allows an authenticated user with topology submission rights to craft malicious component identifiers containing HTML/JavaScript payloads. These payloads propagate through the system and result in stored XSS in the UI's tooltip rendering. This vulnerability affects versions before 2.8.6 and can lead to script execution in privileged users' browsers in multi-tenant environments.
Potential Impact
Successful exploitation allows an authenticated user with topology submission rights to execute arbitrary scripts in the browsers of operators or administrators accessing the Storm UI. This can lead to privilege escalation within the UI context, potentially compromising administrative sessions or data. The impact is limited to environments where less-trusted users can submit topologies and administrators access the UI.
Mitigation Recommendations
A fixed version, Apache Storm 2.8.6, is available and should be applied to remediate this vulnerability. For users unable to upgrade immediately, a monkey patch is recommended to HTML-escape all API-supplied values before insertion into the UI's tooltip HTML strings. Additionally, restricting topology submission to trusted users via Nimbus ACLs is advised as a defense-in-depth measure. Detailed patching guidance is provided in the 2.8.6 release notes.
CVE-2026-35565: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Apache Software Foundation Apache Storm UI
Description
Stored Cross-Site Scripting (XSS) via Unsanitized Topology Metadata in Apache Storm UI Versions Affected: before 2.8.6 Description: The Storm UI visualization component interpolates topology metadata including component IDs, stream names, and grouping values directly into HTML via innerHTML in parseNode() and parseEdge() without sanitization at any layer. An authenticated user with topology submission rights could craft a topology containing malicious HTML/JavaScript in component identifiers (e.g., a bolt ID containing an onerror event handler). This payload flows through Nimbus → Thrift → the Visualization API → vis.js tooltip rendering, resulting in stored cross-site scripting. In multi-tenant deployments where topology submission is available to less-trusted users but the UI is accessed by operators or administrators, this enables privilege escalation through script execution in an admin's browser session. Mitigation: 2.x users should upgrade to 2.8.6. Users who cannot upgrade immediately should monkey-patch the parseNode() and parseEdge() functions in the visualization JavaScript file to HTML-escape all API-supplied values including nodeId, :capacity, :latency, :component, :stream, and :grouping before interpolation into tooltip HTML strings, and should additionally restrict topology submission to trusted users via Nimbus ACLs as a defense-in-depth measure. A guide on how to do this is available in the release notes of 2.8.6. Credit: This issue was discovered while investigating another report by K.
CVSS v3.1
Score 5.4medium
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Apache Storm UI's visualization component improperly neutralizes input during web page generation by directly interpolating topology metadata into HTML via innerHTML without sanitization. This allows an authenticated user with topology submission rights to craft malicious component identifiers containing HTML/JavaScript payloads. These payloads propagate through the system and result in stored XSS in the UI's tooltip rendering. This vulnerability affects versions before 2.8.6 and can lead to script execution in privileged users' browsers in multi-tenant environments.
Potential Impact
Successful exploitation allows an authenticated user with topology submission rights to execute arbitrary scripts in the browsers of operators or administrators accessing the Storm UI. This can lead to privilege escalation within the UI context, potentially compromising administrative sessions or data. The impact is limited to environments where less-trusted users can submit topologies and administrators access the UI.
Mitigation Recommendations
A fixed version, Apache Storm 2.8.6, is available and should be applied to remediate this vulnerability. For users unable to upgrade immediately, a monkey patch is recommended to HTML-escape all API-supplied values before insertion into the UI's tooltip HTML strings. Additionally, restricting topology submission to trusted users via Nimbus ACLs is advised as a defense-in-depth measure. Detailed patching guidance is provided in the 2.8.6 release notes.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- apache
- Date Reserved
- 2026-04-03T15:14:12.281Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69dcbf1a82d89c981f9a03e8
Added to database: 4/13/2026, 10:02:02 AM
Last enriched: 4/13/2026, 10:16:48 AM
Last updated: 5/29/2026, 8:18:59 PM
Views: 78
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