CVE-2021-39211
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 · uneditedGLPI is a free Asset and IT management software package. Starting in version 9.2 and prior to version 9.5.6, the telemetry endpoint discloses GLPI and server information. This issue is fixed in version 9.5.6. As a workaround, remove the file `ajax/telemetry.php`, which is not needed for usual functions of GLPI.
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 confidenceThe GLPI telemetry endpoint in versions 9.2 through 9.5.5 exposes sensitive GLPI installation details and server information, potentially aiding attackers in reconnaissance and planning further attacks.
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>= 9.2, < 9.5.6CVSS 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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 checksWork through these to decide whether this CVE applies to you.
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Determine installed GLPI versionLocate the version file in the GLPI root directory (typically version.php or inc/ defines.php) and read the $CFG_GLPI['version'] or $VERSION variable to identify the exact version number.Affected if The installed version is greater than or equal to 9.2 and less than 9.5.6.
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Locate the telemetry endpoint fileCheck if the file ajax/telemetry.php exists in the GLPI web root directory using filesystem inspection or a directory listing.Affected if The file ajax/telemetry.php exists in the GLPI installation.
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Verify endpoint accessibilityAttempt an HTTP request to the telemetry endpoint (e.g., GET /ajax/telemetry.php or /glpi/ajax/telemetry.php depending on installation path) using curl or a browser to confirm it responds.Affected if The endpoint returns HTTP 200 OK and exposes server or installation details.
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Check telemetry configurationInspect the GLPI configuration file (config.php or config_db.php) for telemetry-related settings or examine the telemetry.php file content to see if it returns sensitive information without authentication.Affected if The telemetry endpoint returns sensitive system information such as PHP version, database type, server OS, or GLPI configuration details without requiring authentication.
A user is affected if their GLPI installation version is 9.2 or higher but below 9.5.6 AND the ajax/telemetry.php file is present and accessible, as this combination allows unauthenticated exposure of sensitive server and installation details.
Generated from the published advisory. Verify against your own configuration.
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 · scoped9.5.6
Upgrade to GLPI 9.5.6 or later, or remove the ajax/telemetry.php file as a workaround since it is not required for normal GLPI operation.
9.5.6
- Upgrade GLPI to version 9.5.6 or later to resolve the information exposure vulnerability in the telemetry endpoint
- As an alternative workaround (if upgrading is not immediately possible), remove the file ajax/telemetry.php from the GLPI installation directory
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation1.0 h
- Implementation1.0 h
- Testing1.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-39211 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-39211 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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