Iphone OsOperating system · Apple

CVE-2011-0228

HIGH · 7.5 CVSS v2.0 Published 2011-08-29
Fix available
A fix is available. Upgrade to after 4.2.9 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges 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
The Data Security component in Apple iOS before 4.2.10 and 4.3.x before 4.3.5 does not check the basicConstraints parameter during validation of X.509 certificate chains, which allows man-in-the-middle attackers to spoof an SSL server by using a non-CA certificate to sign a certificate for an arbitrary domain.

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

The Data Security component in iOS before 4.2.10 and 4.3.x before 4.3.5 fails to validate the basicConstraints extension in X.509 certificate chains, allowing a man-in-the-middle attacker to spoof SSL servers using a non-CA certificate to sign certificates for arbitrary domains.

MitigationUpdate iOS devices to version 4.2.10 or 4.3.5 or later to patch the certificate validation vulnerability.

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
Iphone OsOperating system
Affected:<= 4.2.9= 1.0.0= 1.0.1= 1.0.2= 1.1.0= 1.1.1= 1.1.2= 1.1.3= 1.1.4= 1.1.5= 2.0= 2.0.0

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
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:L/Au:N/C:P/I:P/A:P

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. Check the iOS version installed on the device
    Go to Settings > General > About > Version on the iOS device, or use iTunes to check the device summary
    Affected if The version is 4.2.9 or lower, OR a version in the 4.3.x family before 4.3.5 (such as 4.3.0 through 4.3.4)
  2. Confirm the device is an Apple iOS product
    Verify the device is an iPhone, iPad, or iPod Touch running Apple's iOS operating system
    Affected if The device is not running iOS (for example, Android, BlackBerry, or other platforms are not affected by this specific vulnerability)
  3. Identify if the device uses SSL/TLS network connections
    Review installed applications and network usage - the vulnerability affects Data Security component used when iOS devices make SSL/TLS connections to servers
    Affected if The device makes SSL/TLS connections; the vulnerability is in the certificate validation logic for secure network communications

The device is affected if it runs iOS version 4.2.9 or lower, or any iOS 4.3.x version before 4.3.5, and uses SSL/TLS network communications where certificate validation occurs.

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.

From vendor data
Upgrade available Upgrade to a release after 4.2.9
Interim mitigation

Update iOS devices to version 4.2.10 or 4.3.5 or later to patch the certificate validation vulnerability.

Fix this in Iphone Os Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2011-0228 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2011-0228 in production — separate from our analysis above.

No notes yet

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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