CVE-2011-5241
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 · uneditedServices_Twitter 0.6.3 does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
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 confidenceServices_Twitter 0.6.3, a PHP library for Twitter API communication, fails to perform hostname verification on SSL/TLS certificates. The library accepts any valid X.509 certificate without validating that the certificate's Common Name (CN) or subjectAltName matches the expected hostname (api.twitter.com). This enables man-in-the-middle attackers to intercept encrypted connections by presenting a valid certificate for an attacker-controlled domain.
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= 0.6.3CVSS 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
- M
- Authentication
- None
- Confidentiality
- Partial
- Integrity
- Partial
- Availability
- None
AV:N/AC:M/Au:N/C:P/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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Locate Services_Twitter library in your codebaseSearch for files containing 'Services_Twitter' or check your PHP include paths for the Services directory. Look for a Twitter.php or similar file from the Services_Twitter package.Affected if The library files are present in your application.
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Identify the installed version of Services_TwitterCheck the version declaration in the library's main file (often at the top of Twitter.php), in composer.json if using Composer, or in any package metadata files. The affected version is exactly 0.6.3.Affected if The version is 0.6.3.
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Inspect SSL/TLS verification configuration in HTTP client callsSearch the codebase for curl_setopt or similar HTTP client calls made by or for the Services_Twitter library. Specifically look for CURLOPT_SSL_VERIFYHOST and CURLOPT_SSL_VERIFYPEER settings.Affected if CURLOPT_SSL_VERIFYHOST is set to 0, or CURLOPT_SSL_VERIFYHOST is not explicitly set (defaulting to insecure behavior in older PHP versions), or SSL verification is otherwise disabled.
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Verify if connections to Twitter API use hostname verificationReview the library code that establishes HTTPS connections to api.twitter.com. Check whether the certificate is validated against the expected hostname (api.twitter.com) through the SSL configuration.Affected if The code does not validate that the certificate CN or subjectAltName matches api.twitter.com.
You are affected if Services_Twitter version 0.6.3 is installed and SSL hostname verification (CURLOPT_SSL_VERIFYHOST) is disabled or not properly configured in the library's HTTP client settings.
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 the library to enable proper SSL certificate hostname verification, typically by setting CURLOPT_SSL_VERIFYHOST to 2 (or equivalent) in the HTTP client configuration, ensuring certificates are validated against the expected server hostname.
- Consultation2.0 h
- Implementation3.0 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 $2,512.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-5241 — 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-2011-5241 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