Altium LiveApplication · Altium

CVE-2026-1009

MEDIUM · 5.4 CVSS v3.1 Published 2026-01-15
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A stored cross-site scripting (XSS) vulnerability exists in the Altium Forum due to missing server-side input sanitization in forum post content. An authenticated attacker can inject arbitrary JavaScript into forum posts, which is stored and executed when other users view the affected post. Successful exploitation allows the attacker’s payload to execute in the context of the victim’s authenticated Altium 365 session, enabling unauthorized access to workspace data, including design files and workspace settings. Exploitation requires user interaction to view a malicious forum post.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A stored cross-site scripting (XSS) vulnerability exists in Altium Forum where missing server-side input sanitization allows authenticated attackers to inject malicious JavaScript into forum posts. When users view these posts, the payload executes within their authenticated session context, enabling unauthorized access to Altium 365 workspace data including design files and settings.

MitigationImplement strict server-side input validation and output encoding for all forum post content, utilizing allowlist validation and context-appropriate escaping to neutralize executable scripts.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Altium LiveApplication
Affected:= 1.2.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Altium Live version
    Access the Altium Live administration panel or check the software's built-in 'About' / version information. Alternatively, query the installation directory for version metadata files or check the product information displayed on the login page.
    Affected if The installed version is exactly 1.2.2
  2. Verify forum feature is active
    Confirm that the Altium Forum module is enabled and accessible within the Altium Live environment. Check the application dashboard or configuration settings for forum status.
    Affected if The forum feature is enabled and accessible to users
  3. Confirm authentication capability
    Attempt to log in to Altium Live or verify that user accounts with forum posting privileges exist. The vulnerability requires an authenticated attacker to inject the payload.
    Affected if User authentication to the forum is possible and posting privileges are available
  4. Inspect forum post content for injection points
    Review forum post submission mechanisms and examine stored posts in the database or through the forum interface. Look for posts containing HTML, JavaScript, or script-related tags in content fields.
    Affected if Forum posts accept and store raw HTML/script content without server-side sanitization being visible in the output

A user is affected if Altium Live version 1.2.2 is running with the forum feature enabled and accessible to authenticated users, as the missing server-side input sanitization allows stored XSS to execute when other users view the malicious posts.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict server-side input validation and output encoding for all forum post content, utilizing allowlist validation and context-appropriate escaping to neutralize executable scripts.

Fix this in Altium Live Scoped from the published advisory
  • Consultation3.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
17.0 hours of engineering $3,000
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-1009 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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