SafariWeb browser · Apple

CVE-2011-1344

MEDIUM · 6.8 CVSS v2.0 Published 2011-03-10
Fix available
A fix is available. Upgrade to after 5.0.4 or later.
See remediation →
77/100
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
Use-after-free vulnerability in WebKit, as used in Apple Safari before 5.0.5; iOS before 4.3.2 for iPhone, iPod, and iPad; iOS before 4.2.7 for iPhone 4 (CDMA); and possibly other products allows remote attackers to execute arbitrary code by adding children to a WBR tag and then removing the tag, related to text nodes, as demonstrated by Chaouki Bekrar during a Pwn2Own competition at CanSecWest 2011.

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

Use-after-free vulnerability in WebKit's handling of WBR tag manipulation. Attackers add children to a WBR element, then remove the element while its text node children still hold references, causing the freed memory to be accessed leading to arbitrary code execution.

MitigationUpdate Apple Safari to version 5.0.5 or later, and update iOS devices to version 4.3.2 or later (or latest patched versions). This is a client-side browser vulnerability requiring only software updates.

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
SafariWeb browser
Affected:<= 5.0.4= 1.0= 1.0.0= 1.0.0b1= 1.0.0b2= 1.0.1= 1.0.2= 1.0.3= 1.1= 1.1.0= 1.1.1= 1.2
Iphone OsOperating system
Affected:<= 4.3.1= 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
M
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:M/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 Safari version on macOS
    Open Safari, click the Safari menu in the menu bar, then select 'About Safari'. The version number is displayed in the window that opens.
    Affected if The version listed is 5.0.4 or lower, or matches any of these versions: 1.0, 1.0.0, 1.0.0b1, 1.0.0b2, 1.0.1, 1.0.2, 1.0.3, 1.1, 1.1.0, 1.1.1, or 1.2
  2. Check iOS version on iPhone or iPad
    Open the Settings app, tap 'General', then tap 'About'. The version number is displayed next to 'Version'.
    Affected if The version listed is 4.3.1 or lower, or matches any of these versions: 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, or 2.0.0
  3. Confirm WebKit-based browser usage
    This vulnerability exists in WebKit, which powers Safari and mobile browsers on iOS. If using a third-party browser on iOS, verify whether it uses WebKit by checking the browser's settings or about information.
    Affected if The browser is Safari on macOS or any WebKit-based browser on iOS, and the version falls within the affected ranges

You are affected if Safari version is 5.0.4 or lower, or iOS version is 4.3.1 or lower (or specific older versions listed), since the vulnerability requires the WBR tag manipulation to occur in a WebKit-based browser within those version ranges.

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 5.0.4
Interim mitigation

Update Apple Safari to version 5.0.5 or later, and update iOS devices to version 4.3.2 or later (or latest patched versions). This is a client-side browser vulnerability requiring only software updates.

Fix this in Safari Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

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dbcve dependency scanner

Check whether your project pulls in CVE-2011-1344 — 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-2011-1344 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