MoodleCMS
CVE-2011-4588
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 · uneditedThe ip_in_range function in mnet/lib.php in MNET in Moodle 1.9.x before 1.9.15 uses an incorrect data type, which allows remote attackers to bypass intended IP address restrictions via an XMLRPC request.
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 confidenceThe ip_in_range function in MNET (Moodle's networking module) uses an incorrect data type for IP address comparison, allowing remote attackers to bypass IP-based access restrictions through specially crafted XMLRPC requests.
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
MoodleCMS
= 1.9.1= 1.9.2= 1.9.3= 1.9.4= 1.9.5= 1.9.6= 1.9.7= 1.9.8= 1.9.9= 1.9.10= 1.9.11= 1.9.12CVSS 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
- Authentication
- None
- Confidentiality
- None
- Integrity
- Partial
- Availability
- None
AV:N/AC:L/Au:N/C:N/I:P/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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Identify the installed Moodle versionLocate the version.php file in your Moodle installation directory (typically in the root or lib/ folder) and read the $release or $version variableAffected if The version number begins with 1.9 and falls between 1.9.1 and 1.9.12 inclusive
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Verify the MNET networking module is enabledLog into the Moodle administration panel and navigate to Plugins > Networking > Manage peers, or check the database table mdl_mnet_host for active entriesAffected if MNET module is active and there are configured network peers or remote hosts
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Confirm XMLRPC protocol is accessibleCheck if the MNET XMLRPC service is exposed by attempting to access the mnet/xmlrpc/server.php endpoint or reviewing web server access logs for requests to this endpointAffected if XMLRPC requests to MNET are being accepted by the server
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Examine the ip_in_range function implementationLocate the file containing the ip_in_range function within the MNET module (typically in lib/mnet/ or similar) and inspect the code for IP address comparison logicAffected if The function uses string or integer comparison operators (like == or <) directly on IP addresses without proper ip2long() conversion
Your Moodle installation is affected if it runs version 1.9.1 through 1.9.12, has MNET networking enabled with XMLRPC access, and contains the vulnerable ip_in_range function using incorrect data type handling for IP comparisons.
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.
From vendor dataUpdate to Moodle 1.9.15 or later which contains the corrected ip_in_range function with proper IP address data type handling.
Fix this in Moodle
Scoped from the published advisory
- Consultation2.0 h
- Implementation1.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,936.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-4588 — 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-2011-4588 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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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.
- 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
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