Apple iOS up to 10.3.3 libexpat xml external entity reference

CVSS Meta Temp Score
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CTI Interest Score
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7.2$5k-$25k0.00

A vulnerability was found in Apple iOS up to 10.3.3 (Smartphone Operating System) and classified as critical. Affected by this issue is an unknown functionality of the component libexpat. The manipulation with an unknown input leads to a xml external entity reference vulnerability. Using CWE to declare the problem leads to CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. Impacted is availability. CVE summarizes:

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in an infinite loop using a malformed external entity definition from an external DTD.

The bug was discovered 06/18/2017. The weakness was published 09/25/2017 by Rhodri James as HT208112 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is handled as CVE-2017-9233 since 05/26/2017. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 01/19/2021). It is expected to see the exploit prices for this product increasing in the near future. The advisory points out:

Multiple issues were addressed by updating to version 2.2.1

The vulnerability was handled as a non-public zero-day exploit for at least 37 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 109594 (FreeBSD : python 2.7 -- multiple vulnerabilities (8719b935-8bae-41ad-92ba-3c826f651219)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 170320 (SUSE Enterprise Linux Security Update for expat (SUSE-SU-2017:2299-1)).

Upgrading to version 11 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (109594). Similar entries are available at 89749, 90431, 99039 and 104507.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

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

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Xml external entity reference
CWE: CWE-611 / CWE-610
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 109594
Nessus Name: FreeBSD : python 2.7 -- multiple vulnerabilities (8719b935-8bae-41ad-92ba-3c826f651219)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 801105
OpenVAS Name: Apple Mac OS X Multiple Vulnerabilities-HT208144
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: iOS 11

Timelineinfo

05/26/2017 🔍
06/18/2017 +23 days 🔍
06/26/2017 +8 days 🔍
07/25/2017 +29 days 🔍
09/25/2017 +62 days 🔍
09/25/2017 +0 days 🔍
10/23/2017 +28 days 🔍
05/07/2018 +196 days 🔍
01/19/2021 +988 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT208112
Researcher: Rhodri James
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-9233 (🔍)
OVAL: 🔍

SecurityTracker: 1039427
SecurityFocus: 99276 - Expat CVE-2017-9233 XML External Entity Denial of Service Vulnerability

scip Labs: https://www.scip.ch/en/?labs.20150917
See also: 🔍

Entryinfo

Created: 10/23/2017 11:20
Updated: 01/19/2021 15:12
Changes: 10/23/2017 11:20 (70), 11/29/2019 09:46 (17), 01/19/2021 15:12 (3)
Complete: 🔍

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