Apple MacOS X/iOS prior OS X 10.9/iOS 7 CoreText API Arabic Characters denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Apple MacOS X and iOS. The impacted element is an unknown function of the component CoreText API. This manipulation as part of Arabic Characters causes denial of service. Furthermore, an exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple MacOS X and iOS (Smartphone Operating System). It has been declared as critical. Affected by this vulnerability is an unknown code of the component CoreText API. The manipulation as part of a Arabic Characters leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability.

The weakness was published 08/28/2013 by adamzegelin as Rendering bug crashes OS X, iOS apps with string of Arabic characters as confirmed posting (Website). The advisory is shared at news.ycombinator.com. The public release happened without involvement of Apple. The posting contains:

Some Mac and iOS device users on Twitter were only half joking when labeling the string the "unicode of death."
The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are unknown but a public exploit is available. The advisory points out:
Security researchers, meanwhile, have been poring over crash dumps like this one for signs that the bug could be used for even more nefarious purposes, such as remotely executing malicious code on a vulnerable device.

A public exploit has been developed by adamzegelin in Arabic and been published immediately after the advisory. It is possible to download the exploit at zhovner.com. It is declared as highly functional. We expect the 0-day to have been worth approximately $25k-$100k. The advisory illustrates:

Tweets and other social networking dispatches were enough to cause browsers to crash, so within a few hours of the bug becoming public, Facebook was already preventing the characters from being posted to user walls and timelines by displaying [a] message.

Upgrading to version OS X 10.9 or iOS 7 eliminates this vulnerability. The posting contains the following remark:

This translated habrahabr.ru post about the bug claims that the issue has been fixed in both OS X 10.9 and iOS 7, so affected users who also happen to be early adopters of new Apple software should be able to get a fix soon. However, there's no word on whether future updates to iOS 6 or OS X 10.8 will fix the issue for users who can't or don't want to upgrade.

Additional details are provided at arstechnica.com. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Apple Mac OS X 10.8.4
  • Apple iOS 6.1.3

Productinfo

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Website

CPE 2.3info

CPE 2.2info

Screenshot

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Highly functional
Author: adamzegelin
Programming Language: 🔍
Download: 🔍
Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Upgrade: MacOS X/iOS OS X 10.9/iOS 7

Timelineinfo

08/28/2013 🔍
08/28/2013 +0 days 🔍
09/03/2013 +6 days 🔍
09/22/2022 +3306 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: Rendering bug crashes OS X, iOS apps with string of Arabic characters
Researcher: adamzegelin
Status: Confirmed

GCVE (VulDB): GCVE-100-10105
scip Labs: https://www.scip.ch/en/?labs.20180712
Misc.: 🔍

Entryinfo

Created: 09/03/2013 19:37
Updated: 09/22/2022 15:29
Changes: 09/03/2013 19:37 (57), 05/08/2018 09:03 (2), 09/22/2022 15:29 (2)
Complete: 🔍
Cache ID: 216:286:103

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