PHP up to 5.2.6 Filters mbfilter_htmlent.c memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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9.0$0-$5k0.00

A vulnerability was found in PHP (Programming Language Software). It has been classified as critical. Affected is an unknown part in the library ext/mbstring/libmbfl/filters/mbfilter_htmlent.c of the component Filters. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Heap-based buffer overflow in ext/mbstring/libmbfl/filters/mbfilter_htmlent.c in the mbstring extension in PHP 4.3.0 through 5.2.6 allows context-dependent attackers to execute arbitrary code via a crafted string containing an HTML entity, which is not properly handled during Unicode conversion, related to the (1) mb_convert_encoding, (2) mb_check_encoding, (3) mb_convert_variables, and (4) mb_parse_str functions.

The bug was discovered 08/05/2008. The weakness was released 12/23/2008 (Website). The advisory is shared for download at us-cert.gov. This vulnerability is traded as CVE-2008-5557 since 12/15/2008. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 140 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 78229 (F5 Networks BIG-IP : PHP vulnerability (SOL9761)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family F5 Networks Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 185076 (HP-UX Running Apache Web Server Suite Multiple Vulnerabilities (HPSBUX02431)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 3 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (49753) and Tenable (78229). Entries connected to this vulnerability are available at 23858, 30376, 38768 and 40710.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

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CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.0

VulDB Base Score: 10.0
VulDB Temp Score: 9.0
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VulDB Reliability: 🔍

CVSSv2info

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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Proof-of-Concept

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Nessus ID: 78229
Nessus Name: F5 Networks BIG-IP : PHP vulnerability (SOL9761)
Nessus File: 🔍
Nessus Risk: 🔍
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OpenVAS ID: 63954
OpenVAS Name: Debian Security Advisory DSA 1789-1 (php5)
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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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Countermeasuresinfo

Recommended: Upgrade
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Timelineinfo

08/05/2008 🔍
08/05/2008 +0 days 🔍
12/15/2008 +132 days 🔍
12/21/2008 +6 days 🔍
12/22/2008 +1 days 🔍
12/23/2008 +1 days 🔍
12/23/2008 +0 days 🔍
01/04/2009 +12 days 🔍
03/12/2009 +67 days 🔍
10/10/2014 +2038 days 🔍
03/17/2015 +158 days 🔍
08/23/2019 +1620 days 🔍

Sourcesinfo

Product: php.org

Advisory: us-cert.gov
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2008-5557 (🔍)
OVAL: 🔍

X-Force: 49753
SecurityTracker: 1021482
Vulnerability Center: 20367 - PHP Mbstring Extension Remote Code Execution Vulnerability via a Crafted HTML Entity, High
SecurityFocus: 32948 - PHP 'mbstring' Extension Buffer Overflow Vulnerability
Secunia: 34642
OSVDB: 51477 - CVE-2008-5557 - PHP - Buffer Overflow Issue
Vupen: ADV-2009-1297

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Entryinfo

Created: 03/17/2015 16:11
Updated: 08/23/2019 08:02
Changes: 03/17/2015 16:11 (76), 08/23/2019 08:02 (13)
Complete: 🔍

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