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Chamilo LmsApplication · Chamilo

CVE-2021-35413

HIGH · 8.8 CVSS v3.1 Published 2021-12-03
Fix available
A fix is available. Upgrade to after 1.11.16 or later.
See remediation →
94/100
Remediation priority · Urgent
Public exploit Remotely reachable Zero-click Patch available

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 remote code execution (RCE) vulnerability in course_intro_pdf_import.php of Chamilo LMS v1.11.x allows authenticated attackers to execute arbitrary code via a crafted .htaccess file.

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
How this class of weakness works · CWE-862

The application checks who you are but not whether you're allowed to perform a given action, so any authenticated user can reach things meant for others. This is the classic “change the ID in the URL” bug. The fix is an authorization check on every request, evaluated against the acting user's permissions.

General guidance for the missing authorization class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
Chamilo LmsApplication
Affected:>= 1.11.0, <= 1.11.16

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
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

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
Upgrade available Upgrade to a release after 1.11.16
Vendor patch github.com →
Recommended fix Moderate confidence

Chamilo LMS 1.11.18 or later

  1. 1. Backup your current Chamilo LMS installation and database before performing any upgrade.
  2. 2. Download Chamilo LMS version 1.11.18 or later from the official Chamilo website (https://chamilo.org) or GitHub repository.
  3. 3. Extract the new version files and replace the existing installation files, preserving your configuration and custom files as needed.
  4. 4. Run the database upgrade script if required by following the upgrade instructions in the Chamilo documentation.
  5. 5. Verify the course_intro_pdf_import.php file has been updated and that proper authorization checks are now in place.
  6. 6. Test the import functionality to ensure the vulnerability is remediated and the feature still works correctly.
  7. 7. Clear any caches and ensure the application is functioning properly.
Caveat Review Chamilo LMS 1.11.17+ release notes for any changes that may affect your custom plugins or integrations

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

We can identify the exact fixed release, upgrade, and verify it in staging — typical engagement from $1,950. Get the upgrade done

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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-2021-35413 in production — separate from our analysis above.

No notes yet

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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