dbcve.org
Path TraversalWeakness · CWE-22

CVE-2026-11431

HIGH · 8.3 CVSS v4.0 Published 2026-06-05
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
89/100
Remediation priority · High
Remotely reachable Zero-click

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 path traversal vulnerability exists in the Projects Service download endpoint shared by Altium Enterprise Server and Altium 365. An authenticated user can supply a crafted path parameter that bypasses validation, allowing arbitrary files (including entire directories returned as archives) to be read from the server filesystem. Because the readable files include service configuration and credential material, exploitation can be used to gather information enabling further compromise. The issue can be combined with CVE-2026-11424 to reach the cloud-side endpoint. On multi-tenant Altium 365 deployments, the readable configuration could have exposed credentials shared across services. Altium Enterprise Server is fixed in 8.1.1; the issue has been remediated in Altium 365 at the service level.

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 · high confidence

Path traversal vulnerability in the Projects Service download endpoint of Altium Enterprise Server and Altium 365 allows authenticated users to bypass path validation and read arbitrary files from the server filesystem, including service configuration and credential material.

MitigationUpdate Altium Enterprise Server to version 8.1.1 or later; Altium 365 has been remediated at the service level. Review access logs for signs of exploitation and rotate any exposed credentials.

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

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
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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 installed Altium product and version
    Locate the Altium Enterprise Server or Altium 365 installation and retrieve its version number from the application metadata, about page, or installation directory.
    Affected if Running Altium Enterprise Server version earlier than 8.1.1, or an Altium 365 version without the vendor-provided patch.
  2. Confirm Projects Service is enabled
    Check the Altium server configuration or services panel to verify the Projects Service component is installed and active.
    Affected if The Projects Service module is present and running on the server.
  3. Verify authenticated user access to download endpoint
    Log into the system as an authenticated user and attempt to access the Projects Service download functionality using a standard file path parameter.
    Affected if The download endpoint accepts path parameters from authenticated sessions without blocking traversal sequences.
  4. Review access controls on file download functionality
    Examine the server's web endpoint configuration or API settings for the Projects Service download route to confirm path traversal validation is absent or inadequate.
    Affected if The endpoint permits directory traversal characters (..) in the file path parameter.

A user is affected if running Altium Enterprise Server below version 8.1.1 or an unpatched Altium 365 instance with the Projects Service download endpoint accessible to authenticated users.

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.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Update Altium Enterprise Server to version 8.1.1 or later; Altium 365 has been remediated at the service level. Review access logs for signs of exploitation and rotate any exposed credentials.

Recommended fix High confidence

Altium Enterprise Server 8.1.1 or later

  1. 1. Identify the currently installed Altium Enterprise Server version by checking the system administration panel or installed software version
  2. 2. If running a version earlier than 8.1.1, download Altium Enterprise Server version 8.1.1 or later from the official Altium portal
  3. 3. Schedule a maintenance window following organizational change management procedures
  4. 4. Back up the current installation, including configuration files and databases
  5. 5. Install version 8.1.1 following the standard Altium upgrade documentation
  6. 6. Verify the installation completed successfully and the service is running
  7. 7. Confirm the path traversal vulnerability is resolved by testing that the Projects Service download endpoint properly validates path parameters
  8. 8. For Altium 365 users: no action required as the issue has been remediated at the service level by Altium
Caveat Review Altium 8.1.1 release notes for any configuration or workflow changes that may impact existing processes

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,480
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,968.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-11431 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2026-11431 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data