CVE-2025-34281Public exploitNetwork attack vectorHinoki check available

Cross-user script execution via unsandboxed SVG responses

Published Oct 17, 2025 · Updated Oct 17, 2025

Stored XSS in ThingsBoard before 4.2.1 allows remote authenticated users to execute JavaScript in other users' sessions. ImageController returns uploaded SVG files using their media type without a restrictive Content-Security-Policy header, allowing embedded scripts to run through a public image URL or dashboard iframe. A tenant administrator must upload the SVG, and a victim must view it; the script can access session data and perform actions as that victim.

CVSS severity6.2
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored XSS in ThingsBoard before 4.2.1 allows remote authenticated users to execute JavaScript in other users' sessions. ImageController returns uploaded SVG files using their media type without a restrictive Content-Security-Policy header, allowing embedded scripts to run through a public image URL or dashboard iframe. A tenant administrator must upload the SVG, and a victim must view it; the script can access session data and perform actions as that victim.

The record

CVE
CVE-2025-34281
Published
Oct 17, 2025
Updated
Oct 17, 2025
Vendor
ThingsBoard
Product
ThingsBoard
Classifications
CWE-79, CAPEC-592, T1528
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 17, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 17, 2025Record 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=0 <4.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

ThingsBoard · ThingsBoardversion=0 <4.2.1

Published CVSS scores

6.2CheckmarxCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:H/SI:L/SA:N
5.4NVDCVSS:3.1/AV:N/AC:L/PR:L/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS
T1528Steal Application Access Token

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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